diff --git a/packages/ember-htmlbars/lib/node-managers/component-node-manager.js b/packages/ember-htmlbars/lib/node-managers/component-node-manager.js
index f19055cfcd9..e6af331b6f2 100644
--- a/packages/ember-htmlbars/lib/node-managers/component-node-manager.js
+++ b/packages/ember-htmlbars/lib/node-managers/component-node-manager.js
@@ -75,8 +75,10 @@ ComponentNodeManager.create = function(renderNode, env, options) {
     createOptions._deprecatedFlagForBlockProvided = true;
   }
 
+  let proto = extractPositionalParams(renderNode, component, params, attrs);
+
   // Instantiate the component
-  component = createComponent(component, isAngleBracket, createOptions, renderNode, env, attrs);
+  component = createComponent(component, isAngleBracket, createOptions, renderNode, env, attrs, proto);
 
   // If the component specifies its template via the `layout` or `template`
   // properties instead of using the template looked up in the container, get
@@ -85,7 +87,6 @@ ComponentNodeManager.create = function(renderNode, env, options) {
   layout = result.layout || layout;
   templates = result.templates || templates;
 
-  extractPositionalParams(renderNode, component, params, attrs);
 
   let results = buildComponentTemplate(
     { layout, component, isAngleBracket }, attrs, { templates, scope: parentScope }
@@ -95,30 +96,55 @@ ComponentNodeManager.create = function(renderNode, env, options) {
 };
 
 function extractPositionalParams(renderNode, component, params, attrs) {
-  if (component.positionalParams) {
-    // if the component is rendered via {{component}} helper, the first
-    // element of `params` is the name of the component, so we need to
-    // skip that when the positional parameters are constructed
-    const paramsStartIndex = renderNode.state.isComponentHelper ? 1 : 0;
-    const positionalParams = component.positionalParams;
-    const isNamed = typeof positionalParams === 'string';
-    let paramsStream;
-
-    if (isNamed) {
-      paramsStream = new Stream(() => {
-        return readArray(params.slice(paramsStartIndex));
-      }, 'params');
-
-      attrs[positionalParams] = paramsStream;
-    }
+  let positionalParams = component.positionalParams;
+  let proto;
+
+  if (!positionalParams) {
+    proto = component.proto();
+    positionalParams = proto.positionalParams;
+
+    Ember.deprecate(
+      'Calling `var Thing = Ember.Component.extend({ positionalParams: [\'a\', \'b\' ]});` ' +
+        'is deprecated in favor of `Thing.reopenClass({ positionalParams: [\'a\', \'b\'] });',
+      !positionalParams,
+      { id: 'ember-htmlbars.component-positional-params', until: '2.0.0' }
+    );
+  }
+
+  if (positionalParams) {
+    processPositionalParams(renderNode, positionalParams, params, attrs);
+  }
+
+  // returns `proto` here so that we can avoid doing this
+  // twice for each initial render per component (it is also needed in `createComponent`)
+  return proto;
+}
+
+function processPositionalParams(renderNode, positionalParams, params, attrs) {
+  // if the component is rendered via {{component}} helper, the first
+  // element of `params` is the name of the component, so we need to
+  // skip that when the positional parameters are constructed
+  const paramsStartIndex = renderNode.state.isComponentHelper ? 1 : 0;
+  const isNamed = typeof positionalParams === 'string';
+  let paramsStream;
 
+  if (isNamed) {
+    paramsStream = new Stream(() => {
+      return readArray(params.slice(paramsStartIndex));
+    }, 'params');
+
+    attrs[positionalParams] = paramsStream;
+  }
+
+  if (isNamed) {
+    for (let i = paramsStartIndex; i < params.length; i++) {
+      let param = params[i];
+      paramsStream.addDependency(param);
+    }
+  } else {
     for (let i = 0; i < positionalParams.length; i++) {
       let param = params[paramsStartIndex + i];
-      if (isNamed) {
-        paramsStream.addDependency(param);
-      } else {
-        attrs[positionalParams[i]] = param;
-      }
+      attrs[positionalParams[i]] = param;
     }
   }
 }
@@ -187,13 +213,11 @@ function configureCreateOptions(attrs, createOptions) {
 }
 
 ComponentNodeManager.prototype.render = function(_env, visitor) {
-  var { component, attrs } = this;
+  var { component } = this;
 
   return instrument(component, function() {
     let env = _env.childWithView(component);
 
-    var snapshot = takeSnapshot(attrs);
-    env.renderer.componentInitAttrs(this.component, snapshot);
     env.renderer.componentWillRender(component);
     env.renderedViews.push(component.elementId);
 
@@ -274,18 +298,18 @@ ComponentNodeManager.prototype.destroy = function() {
   component.destroy();
 };
 
-export function createComponent(_component, isAngleBracket, _props, renderNode, env, attrs = {}) {
+export function createComponent(_component, isAngleBracket, _props, renderNode, env, attrs = {}, proto = _component.proto()) {
   let props = assign({}, _props);
+  let attrsSnapshot;
 
   if (!isAngleBracket) {
     let hasSuppliedController = 'controller' in attrs; // 2.0TODO remove
     Ember.deprecate('controller= is deprecated', !hasSuppliedController, { id: 'ember-htmlbars.create-component', until: '3.0.0' });
 
-    let snapshot = takeSnapshot(attrs);
-    props.attrs = snapshot;
+    attrsSnapshot = takeSnapshot(attrs);
+    props.attrs = attrsSnapshot;
 
-    let proto = _component.proto();
-    mergeBindings(props, shadowedAttrs(proto, snapshot));
+    mergeBindings(props, shadowedAttrs(proto, attrsSnapshot));
   } else {
     props._isAngleBracket = true;
   }
@@ -295,6 +319,8 @@ export function createComponent(_component, isAngleBracket, _props, renderNode,
 
   let component = _component.create(props);
 
+  env.renderer.componentInitAttrs(component, attrsSnapshot);
+
   // for the fallback case
   component.container = component.container || env.container;
 
diff --git a/packages/ember-htmlbars/tests/integration/component_invocation_test.js b/packages/ember-htmlbars/tests/integration/component_invocation_test.js
index 619bba89609..b046dee19c4 100644
--- a/packages/ember-htmlbars/tests/integration/component_invocation_test.js
+++ b/packages/ember-htmlbars/tests/integration/component_invocation_test.js
@@ -404,7 +404,7 @@ if (isEnabled('ember-views-component-block-info')) {
   });
 }
 
-QUnit.test('static named positional parameters', function() {
+QUnit.test('static named positional parameters [DEPRECATED]', function() {
   registry.register('template:components/sample-component', compile('{{attrs.name}}{{attrs.age}}'));
   registry.register('component:sample-component', Component.extend({
     positionalParams: ['name', 'age']
@@ -415,12 +415,14 @@ QUnit.test('static named positional parameters', function() {
     container: container
   }).create();
 
-  runAppend(view);
+  expectDeprecation(function() {
+    runAppend(view);
+  }, 'Calling `var Thing = Ember.Component.extend({ positionalParams: [\'a\', \'b\' ]});` is deprecated in favor of `Thing.reopenClass({ positionalParams: [\'a\', \'b\'] });');
 
   equal(jQuery('#qunit-fixture').text(), 'Quint4');
 });
 
-QUnit.test('dynamic named positional parameters', function() {
+QUnit.test('dynamic named positional parameters [DEPRECATED]', function() {
   registry.register('template:components/sample-component', compile('{{attrs.name}}{{attrs.age}}'));
   registry.register('component:sample-component', Component.extend({
     positionalParams: ['name', 'age']
@@ -435,7 +437,10 @@ QUnit.test('dynamic named positional parameters', function() {
     }
   }).create();
 
-  runAppend(view);
+  expectDeprecation(function() {
+    runAppend(view);
+  }, 'Calling `var Thing = Ember.Component.extend({ positionalParams: [\'a\', \'b\' ]});` is deprecated in favor of `Thing.reopenClass({ positionalParams: [\'a\', \'b\'] });');
+
   equal(jQuery('#qunit-fixture').text(), 'Quint4');
   run(function() {
     set(view.context, 'myName', 'Edward');
@@ -445,7 +450,7 @@ QUnit.test('dynamic named positional parameters', function() {
   equal(jQuery('#qunit-fixture').text(), 'Edward5');
 });
 
-QUnit.test('static arbitrary number of positional parameters', function() {
+QUnit.test('static arbitrary number of positional parameters [DEPRECATED]', function() {
   registry.register('template:components/sample-component', compile('{{#each attrs.names as |name|}}{{name}}{{/each}}'));
   registry.register('component:sample-component', Component.extend({
     positionalParams: 'names'
@@ -456,14 +461,17 @@ QUnit.test('static arbitrary number of positional parameters', function() {
     container: container
   }).create();
 
-  runAppend(view);
+  expectDeprecation(function() {
+    runAppend(view);
+  }, 'Calling `var Thing = Ember.Component.extend({ positionalParams: [\'a\', \'b\' ]});` is deprecated in favor of `Thing.reopenClass({ positionalParams: [\'a\', \'b\'] });');
+
 
   equal(view.$('#args-3').text(), 'Foo4Bar');
   equal(view.$('#args-5').text(), 'Foo4Bar5Baz');
   equal(view.$('#helper').text(), 'Foo4Bar5Baz');
 });
 
-QUnit.test('dynamic arbitrary number of positional parameters', function() {
+QUnit.test('dynamic arbitrary number of positional parameters [DEPRECATED]', function() {
   registry.register('template:components/sample-component', compile('{{#each attrs.names as |name|}}{{name}}{{/each}}'));
   registry.register('component:sample-component', Component.extend({
     positionalParams: 'names'
@@ -478,7 +486,108 @@ QUnit.test('dynamic arbitrary number of positional parameters', function() {
     }
   }).create();
 
+  expectDeprecation(function() {
+    runAppend(view);
+  }, 'Calling `var Thing = Ember.Component.extend({ positionalParams: [\'a\', \'b\' ]});` is deprecated in favor of `Thing.reopenClass({ positionalParams: [\'a\', \'b\'] });');
+
+  equal(view.$('#direct').text(), 'Foo4');
+  equal(view.$('#helper').text(), 'Foo4');
+  run(function() {
+    set(view.context, 'user1', 'Bar');
+    set(view.context, 'user2', '5');
+  });
+
+  equal(view.$('#direct').text(), 'Bar5');
+  equal(view.$('#helper').text(), 'Bar5');
+});
+
+QUnit.test('static named positional parameters', function() {
+  var SampleComponent = Component.extend();
+  SampleComponent.reopenClass({
+    positionalParams: ['name', 'age']
+  });
+  registry.register('template:components/sample-component', compile('{{attrs.name}}{{attrs.age}}'));
+  registry.register('component:sample-component', SampleComponent);
+
+  view = EmberView.extend({
+    layout: compile('{{sample-component "Quint" 4}}'),
+    container: container
+  }).create();
+
+  runAppend(view);
+
+  equal(jQuery('#qunit-fixture').text(), 'Quint4');
+});
+
+QUnit.test('dynamic named positional parameters', function() {
+  var SampleComponent = Component.extend();
+  SampleComponent.reopenClass({
+    positionalParams: ['name', 'age']
+  });
+
+  registry.register('template:components/sample-component', compile('{{attrs.name}}{{attrs.age}}'));
+  registry.register('component:sample-component', SampleComponent);
+
+  view = EmberView.extend({
+    layout: compile('{{sample-component myName myAge}}'),
+    container: container,
+    context: {
+      myName: 'Quint',
+      myAge: 4
+    }
+  }).create();
+
   runAppend(view);
+
+  equal(jQuery('#qunit-fixture').text(), 'Quint4');
+  run(function() {
+    set(view.context, 'myName', 'Edward');
+    set(view.context, 'myAge', '5');
+  });
+
+  equal(jQuery('#qunit-fixture').text(), 'Edward5');
+});
+
+QUnit.test('static arbitrary number of positional parameters', function() {
+  var SampleComponent = Component.extend();
+  SampleComponent.reopenClass({
+    positionalParams: 'names'
+  });
+
+  registry.register('template:components/sample-component', compile('{{#each attrs.names as |name|}}{{name}}{{/each}}'));
+  registry.register('component:sample-component', SampleComponent);
+
+  view = EmberView.extend({
+    layout: compile('{{sample-component "Foo" 4 "Bar" id="args-3"}}{{sample-component "Foo" 4 "Bar" 5 "Baz" id="args-5"}}{{component "sample-component" "Foo" 4 "Bar" 5 "Baz" id="helper"}}'),
+    container: container
+  }).create();
+
+  runAppend(view);
+
+  equal(view.$('#args-3').text(), 'Foo4Bar');
+  equal(view.$('#args-5').text(), 'Foo4Bar5Baz');
+  equal(view.$('#helper').text(), 'Foo4Bar5Baz');
+});
+
+QUnit.test('dynamic arbitrary number of positional parameters', function() {
+  var SampleComponent = Component.extend();
+  SampleComponent.reopenClass({
+    positionalParams: 'n'
+  });
+  registry.register('template:components/sample-component', compile('{{#each attrs.n as |name|}}{{name}}{{/each}}'));
+  registry.register('component:sample-component', SampleComponent);
+
+  view = EmberView.extend({
+    layout: compile('{{sample-component user1 user2 id="direct"}}{{component "sample-component" user1 user2 id="helper"}}'),
+    container: container,
+    context: {
+      user1: 'Foo',
+      user2: 4
+    }
+  }).create();
+
+  runAppend(view);
+
   equal(view.$('#direct').text(), 'Foo4');
   equal(view.$('#helper').text(), 'Foo4');
   run(function() {
@@ -488,6 +597,13 @@ QUnit.test('dynamic arbitrary number of positional parameters', function() {
 
   equal(view.$('#direct').text(), 'Bar5');
   equal(view.$('#helper').text(), 'Bar5');
+
+  run(function() {
+    set(view.context, 'user2', '6');
+  });
+
+  equal(view.$('#direct').text(), 'Bar6');
+  equal(view.$('#helper').text(), 'Bar6');
 });
 
 QUnit.test('moduleName is available on _renderNode when a layout is present', function() {
@@ -533,7 +649,7 @@ QUnit.test('moduleName is available on _renderNode when no layout is present', f
 });
 
 if (isEnabled('ember-htmlbars-component-helper')) {
-  QUnit.test('{{component}} helper works with positional params', function() {
+  QUnit.test('{{component}} helper works with positional params [DEPRECATED]', function() {
     registry.register('template:components/sample-component', compile('{{attrs.name}}{{attrs.age}}'));
     registry.register('component:sample-component', Component.extend({
       positionalParams: ['name', 'age']
@@ -548,6 +664,37 @@ if (isEnabled('ember-htmlbars-component-helper')) {
       }
     }).create();
 
+    expectDeprecation(function() {
+      runAppend(view);
+    }, 'Calling `var Thing = Ember.Component.extend({ positionalParams: [\'a\', \'b\' ]});` is deprecated in favor of `Thing.reopenClass({ positionalParams: [\'a\', \'b\'] });');
+
+    equal(jQuery('#qunit-fixture').text(), 'Quint4');
+    run(function() {
+      set(view.context, 'myName', 'Edward');
+      set(view.context, 'myAge', '5');
+    });
+
+    equal(jQuery('#qunit-fixture').text(), 'Edward5');
+  });
+
+  QUnit.test('{{component}} helper works with positional params', function() {
+    var SampleComponent = Component.extend();
+    SampleComponent.reopenClass({
+      positionalParams: ['name', 'age']
+    });
+
+    registry.register('template:components/sample-component', compile('{{attrs.name}}{{attrs.age}}'));
+    registry.register('component:sample-component', SampleComponent);
+
+    view = EmberView.extend({
+      layout: compile('{{component "sample-component" myName myAge}}'),
+      container: container,
+      context: {
+        myName: 'Quint',
+        myAge: 4
+      }
+    }).create();
+
     runAppend(view);
     equal(jQuery('#qunit-fixture').text(), 'Quint4');
     run(function() {
diff --git a/packages/ember-metal-views/lib/renderer.js b/packages/ember-metal-views/lib/renderer.js
index 405dfa134e2..3e656592fed 100755
--- a/packages/ember-metal-views/lib/renderer.js
+++ b/packages/ember-metal-views/lib/renderer.js
@@ -136,7 +136,6 @@ Renderer.prototype.setAttrs = function (view, attrs) {
 }; // set attrs the first time
 
 Renderer.prototype.componentInitAttrs = function (component, attrs) {
-  set(component, 'attrs', attrs);
   component.trigger('didInitAttrs', { attrs });
   component.trigger('didReceiveAttrs', { newAttrs: attrs });
 }; // set attrs the first time