Update customization.md

Author: pokey

packages/cursorless-org-docs/src/docs/user/customization.md

@@ -211,27 +211,27 @@ _NOTE that this feature is experimental. Not as thoroughly tested as the rest of
 
 `user.cursorless_custom_command(command: string, *args)`
 
-Run a custom Cursorless command by parsing the specified command string.
+Run a custom Cursorless command by parsing the specified command string. Supports a subset of the Cursorless grammar, with **default** spoken forms (not your custom spoken forms). See https://www.cursorless.org/custom-command-railroad to see the subset of our grammar that we support today.
 
 - Utilizes default Cursorless spoken forms in the command string.
-- Optional target arguments can be interpolated in the command string.
+- Optional target arguments can be interpolated in the command string. (see examples below)
 
 #### Examples
 
-`"scratch"` => `"chuck block"`
+In order to map `"scratch"` to perform `"chuck block"`:
 
 ```talon
 scratch: user.cursorless_custom_command("chuck block")
 ```
 
-`"scratch air"` => `"chuck block air"`
+To map `"scratch air"` => `"chuck block air"`
 
 ```talon
 scratch <user.cursorless_target>:
     user.cursorless_custom_command("chuck block <target>", cursorless_target)
 ```
 
-`"combine air plus bat"` => `"bring block air after bat"`
+To map `"combine air plus bat"` => `"bring block air after bat"`
 
 ```talon
 combine <user.cursorless_target> plus <user.cursorless_target>: