Re: what would you do?
Periolically, my sensei, when demonstrating a technique says, "Now really resist!" And it's usually me he is asking to resist ('cause at 5'11 & 160 lb. I'm the usually biggest student in the lower level class of our small dojo.)
Enevitibly, the harder I resist, the harder I fall, the worse it hurts, etc.
At that, I'm sure Sensei is still holding back, 'cause my ukemi isn't THAT good yet. . . Of course Sensei is not only a yondan, but is also in by far the best physical condition of any 67 year old I know. . .