>The solution [...] is to start them at, say, 9:10am so there's a clean mental stop at 10am.
Unfortunately, I've been in a few meetings scheduled for 9:00 that only really started at 9:10. I think if they were scheduled for 9:10, they would've only started at 9:20...
Haha. I was one of those “set clock fast” people until one day realized that all it did was make the time I was supposed to be somewhere even more ambiguous than before. It never helped me arrive somewhere exactly on time, but certainly contributed to me arriving late because my mind forgot precisely what time my clock was set to relative to real time.
Unfortunately, I've been in a few meetings scheduled for 9:00 that only really started at 9:10. I think if they were scheduled for 9:10, they would've only started at 9:20...