Attach Symbol: Left Hand – Logic Pro keyboard command of the day (KCotD)

  Attach Symbol: Left Hand

Decidedly frustrating. I cannot find anything that indicates which symbol will be attached to a score when using this command. There is no description of what all of the symbols in the part boxes mean. Executing this command with a note selected in a score shows no visible change.

I have watched tutorial videos, read manuals. No help. Can’t find them.