Well, it's been interesting. I went TDY (Army/Air Force for Temporary Duty -- civilians call it a business trip,) so I could be certified as a Video teleconference facilitator.
When I first registered for the class, I did so as my old name, then changed it when 'Karen' became official, so they knew I was coming.
The trip out was pretty much uneventful -- Sacramento to Chicago to Norfolk VA, then get a rental car. Well, there was one incident -- it seems I'd used the rental car company some time before, as [old-name]. Guess what popped up on the paperwork? The clerk kept wanting to know who [old-name] was -- it really seemed to matter to her. I finally had to say, "I'm transgendered..." The male clerk at the next station 'got it', and told her not to worry about it, it was okay, but she seemed very upset/embarrassed/confused/etc., by it.
Check in to the hotel - OK. Dinner the night before class - OK.
The start of class was interesting. One of the students was a testosterone-soaked hyper-virilized male. When the rumours started circulating about me, he seemed a bit uncomfortable, but was pretty much a minority of one and knew it. No one else seemed to care much.
One of the instructors ("S") turned out to be someone who I previously 'knew' via telephone and VTC contact. So I finally get to meet him face-to-face, but as Karen. Interesting...
The instructors and most of the students got the pronouns right most of the time. And the instructors always apologised if they messed up, to which I replied that mistakes do happen and that I really appreciated their effort (now let's move on and get back to class

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There were three instructors -- the one I mentioned earlier, one female ("D") with no active military experience, and one male ("B") who had retired from the army like me. D was a resident, and knew all the good places to go. One day after lunch and before class started, she asked me what being TG was all about, so I gave the standard TG-101 'pitch'. S wandered by and stopped to listen in, and asked a few questions.
I connected with B over our shared Army background. He didn't ask too many questions, seeming to not want to pry. We got along fine, and he praised my technical knowledge.
Being the techno-geek that I am, I passed the course ease.
Karen