interesting, I wish amazon would let me see inside the music theory book.

I'm just curious if they are still using note names and how this teacher is going about things... Because yes it's totally true you don't need to be able to read sheet music in order to understand theory well

Look at a jazz lead sheet for example, where chord voicings aren't usually spelled out (big band being an exception sometimes). Or in analysis e.g I - V7 - iv