I think we need to draw a distinction between antagonizing him and trying to further educate him. His last "apology" still had plenty of things that were not right, and he still needs to learn how to be more sensitive to the trans* community. You're speaking as though he's learned his lesson, LarryC, when, in all likelihood, the only lesson he may have learned is to keep his hands out of that particular hornet's nest.
I'm advocating not calling an asshat an asshat when that provably leads to them being even more of an asshat, which then excuses lots more asshats to be even more asshats. At that point, maybe do, well, anything else? Unless the point is to encourage the asshattery, which, as I said, if true, then fire away. Purely results oriented. No moral judgments.
The bolded issue is his problem to correct, by the way.