Being at a university, we get a fair number of students with other MA backgrounds, and as mentioned before, it the people with limited experience that are the hardest to work with.
Last year, though, we had a judoka who joined us, maybe 18 or 19 years old -- and just a huge burly guy. One evening he was working with another new student, a petite, timid girl who was really struggling to become comfortable on the mat and with all the physical contact.
I forget what the technique was, but Sensei specifically told him to be careful with her and not use the muscling of judo when throwing her.... The next thing we know, he didn't get out of the way of her atemi, and was holding his bloody nose
For some unknow reason, he never did come back after that
. Talk about having your ego burst....
-jon