Clarify compile disabling assets in production

Author: josh

README.md

@@ -88,7 +88,7 @@ Enable expanded asset debugging mode. Individual files will be served to make re
 
 **`config.assets.compile`**
 
-Enables Sprockets compile environment. If disabled, `Rails.application.assets` will be unavailable to any ActionView helpers. View helpers will depend on assets being precompiled to `public/assets` in order to link to them. You can still access the environment by directly calling `Rails.application.assets`.
+Enables Sprockets compile environment. If disabled, `Rails.application.assets` will be `nil` to prevent inadvertent compilation calls. View helpers will depend on assets being precompiled to `public/assets` in order to link to them. Initializer could expecting `Rails.application.assets` during boot should be accessing the environment in a `config.assets.configure` block. See below.
 
 **`config.assets.configure`**