docs; clarify #3597

docs/faq.jade

@@ -25,20 +25,6 @@ block content
     doc.array[3] = 'changed';
     doc.markModified('array');
     doc.save();
-  hr#assign_schemas_to_paths
-  :markdown
-    **Q**. Why doesn't mongoose allow me to directly assign schemas to paths?
-  :js
-    var userSchema = new Schema({ name: String });
-    new Schema({ user: userSchema })
-  :markdown
-    **A**. Schemas have a one-to-one mapping with documents. Documents have `save` and `remove` methods along with their own `pre` and `post` hooks which would lead to code like the following:
-  :js
-    doc.user.save();  // ?
-    doc.user.remove();// ?
-    doc.save()
-  :markdown
-    We've felt that this api would be more confusing than helpful. The counter argument is that arrays of sub-documents already have this functionality, but at best this too leads to confusion (calling `save` on a sub-document is a no-op and exists only to support `pre` save hooks). In the future this is likely to be revisited.
   hr#enable_debugging
   :markdown
     **Q**. How can I enable debugging?
@@ -66,14 +52,19 @@ block content
     **Q**. Should I create/destroy a new connection for each database operation?
 
     **A**. No. Open your connection when your application starts up and leave it open until the application shuts down.
-  hr#overwritemodelerror
+  hr#overwrite-model-error
   :markdown
-    **Q**. Why do I get "OverwriteModelError: Cannot overwrite .. model once compiled" when I use nodemon / a testing framework?
-    It always works when the code loads the first time, but then throws this error from the second load onwards.
+    **Q**. Why do I get "OverwriteModelError: Cannot overwrite .. model once
+    compiled" when I use nodemon / a testing framework?
 
-    **A**. Use `connection.model(..)` instead of `mongoose.model(..)` to create your models.  
-    See [this issue](https://github.com/Automattic/mongoose/issues/1251#issuecomment-11697477) and below:
-    "it works b/c a new connection is created for each of your tests and the model is cached locally within the connection for each. the other way fails b/c models were getting compiled at the mongoose module level for each test, hence the conflicts."
+    **A**. `mongoose.model('ModelName', schema)` requires 'ModelName' to be
+    unique, so you can access the model by using `mongoose.model('ModelName')`.
+    If you put `mongoose.model('ModelName', schema);` in a
+    [mocha `beforeEach()` hook](https://mochajs.org/#hooks), this code will
+    attempt to create a new model named 'ModelName' before **every** test,
+    and so you will get an error. Make sure you only create a new model with
+    a given name **once**. If you need to create multiple models with the
+    same name, create a new connection and bind the model to the connection.
   :js
     var mongoose = require('mongoose');
     var connection = mongoose.createConnection(..);
@@ -90,4 +81,3 @@ block content
 
     If you'd like to contribute to this page, please [visit it](https://github.com/Automattic/mongoose/tree/master/docs/faq.jade) on github and use the [Edit](https://github.com/blog/844-forking-with-the-edit-button) button to send a pull request.
   br
-