Expand on how block editor features should work

docs/designers-developers/developers/themes/theme-json.md

@@ -166,7 +166,14 @@ The list of properties that are currently exposed via this method are:
 
 ### Features
 
-So far, this function is only enabled for the `global` section in `experimental-theme.json`.
+Via the features key we allow controlling some editor and block features according to the following rules:
+- The features within `global` override the default editor settings, which plugins can modify by hooking into the `block_editor_settings` filter on the server.
+- The features within the context of each block override the default block settings, which plugins can modify by hooking into the `blocks.registerBlockType` filter on the client.
+- Block settings take precedence over global settings.
+
+For example, if a feature is enabled for a block by default, although the theme disables it at the global level, the block keeps it enabled. If the theme wants to override a block's default, it has to target that particular block.
+
+So far, this function is enabled only for the `global` section in `lib/experimental-default-theme.json`.
 
 ```
 {
@@ -194,7 +201,7 @@ Then each block can decide to override how they handle block editor features dur
 }
 ```
 
-Moving forward, we plan to integrate overrides targeting individual blocks defined inside `experimental-theme.json` file that would be applied on top of features defined by block authors in `supports` property.
+Moving forward, we plan to integrate overrides targeting individual blocks defined inside a theme specific file (`experimental-theme.json`) that would be applied on top of features defined by block authors in `supports` property.
 
 The list of features that are currently supported are:
 - Paragraph: drop cap.