I don't think I've over prepared. In fact, I'm a tad under prepared. I do not have any issues with the content. I shouldn't since I've attended this course six times since May last year!
The only issue I have was the sequenced activity and the scripted things to say at the right place and time. Since I've have been more spontaneous in my other training sessions, this is quite stressful for me.
But I must say, except for a few minor glitches, it went quite well. I have not been really training for awhile now, and I'm glad I'm doing it again.