Incremental Static Regeneration - docs update explaining surprising behavior

docs/02-app/01-building-your-application/04-caching/index.mdx

@@ -538,6 +538,12 @@ For [dynamic segments](/docs/app/building-your-application/routing/dynamic-route
 
 You can disable caching at request time by using `export const dynamicParams = false` option in a route segment. When this config option is used, only paths provided by `generateStaticParams` will be served, and other routes will 404 or match (in the case of [catch-all routes](/docs/app/building-your-application/routing/dynamic-routes#catch-all-segments)).
 
+#### Incremental Static Regeneration
+Even if you don't have any static routes to render at build time, you still need `generateStaticParams` to return an empty array if you want dynamically generated pages to be cached.
+```jsx
+export const generateStaticParams = async () => [];
+```
+
 See the [`generateStaticParams` API reference](/docs/app/api-reference/functions/generate-static-params).
 
 ### React `cache` function

docs/02-app/02-api-reference/02-file-conventions/route-segment-config.mdx

@@ -84,6 +84,7 @@ export const dynamicParams = true // true | false,
 > **Good to know**:
 >
 > - This option replaces the `fallback: true | false | blocking` option of `getStaticPaths` in the `pages` directory.
+> - Even though this defaults to true, your pages won't be cached unless your layout or page also makes use of `generateStaticParams`, even if it only returns an empty array.
 > - When `dynamicParams = true`, the segment uses [Streaming Server Rendering](/docs/app/building-your-application/routing/loading-ui-and-streaming#streaming-with-suspense).
 > - If the `dynamic = 'error'` and `dynamic = 'force-static'` are used, it'll change the default of `dynamicParams` to `false`.
 

docs/02-app/02-api-reference/04-functions/generate-static-params.mdx

@@ -26,6 +26,7 @@ export default function Page({ params }) {
 > **Good to know**
 >
 > - You can use the [`dynamicParams`](/docs/app/api-reference/file-conventions/route-segment-config#dynamicparams) segment config option to control what happens when a dynamic segment is visited that was not generated with `generateStaticParams`.
+> - You must include `generateStaticParams` even if you only want pages to be cached *after* build time.
 > - During `next dev`, `generateStaticParams` will be called when you navigate to a route.
 > - During `next build`, `generateStaticParams` runs before the corresponding Layouts or Pages are generated.
 > - During revalidation (ISR), `generateStaticParams` will not be called again.