I think this is a big one as well, and would go one step further and say that anyone no matter their place on the spectrum may fail at communication in this way. I bet most junior developers know what I mean, if they've sat in meetings with senior guys talking about something esoteric.

One simple trick, I think, is to avoid extensive use of pronouns. A sentence like "Because of that, it doesn't find it there" might be clear enough when you know the context, but is meaningless if you don't. Filling in "that", "it", "it", and "there" would help tremendously. It will make sentences awkward if you avoid them completely, of course, but I think sentences that contain nothing but pronouns are a red flag.