I don’t think Greg is talking about suing anyone who utters the words "dive buddy". He is talking about other commercial businesses who use his copyrighted business name for their own businesses.
As an example, you may consider yourself an aggressive diver, you may have aggressive dive buddies, you may meet socially and discuss your aggressive diving techniques, but if you buy a boat and turn it into a commercial liveaboard diving boat, you can’t name it Aggressor, nor call your liveaboard website Aggressor.com