Quickest way to add a keyword to a document?

Any suggestions on the quickest way to add one or more keywords to a document?

My preference is to work from the keyboard only, but I haven’t found a keyboard shortcut that gets the job done.

I can get to the keyword pane in the inspector with ^⌥⌘J but haven’t found a way to navigate to the Keyword list from there. Down arrow and tab just seem to get stuck.

This is the best I’ve come up with:

^⌥⌘L and then hit Return.