In one dojo, the senior trainers/practitioners with black trousers removed their trousers in front of the students who then sat down and folded/wrapped up the trousers for the seniors. This I think takes the system of respect too far.
This is only done for Shihans. It is a sign of respect and is an honor to be the person folding the hakama for him or her.
"...It's possible to go overboard - I've been in dojo where we were expected to watch in seiza if the shihan came over to help and was demonstrating with our partner, and then to do a bow in seiza..."
This is how things are done at Aikikai Honbu dojo. I would assume that they know the proper etiquette.