Kimura, because I use it a lot also to sweep and pass the half guard.

Where is it in the classroom? Can't find it.

Very good idea! It seems very logical. In fact, this is a bit what we already use when we do the upa where we block the opponent's arm under the armpit, we walk with the shoulders backward, which has the effect of stretching the opponent's body forward. It is then much easier to roll. Applying the same principle to this upa is a very good idea. And as @Rich Q says, this exactly respects the principles of Rickson's upa. And even if you don't really move your head forward much, it's a good way to visualize the ideal angle and movement. I can't wait to try this.

The place i train is late evening. I have no choice But if i can choose i'll say late morning.

I agree. Making someone understand that to be relax is important isn't easy. Another thing that's not easy is explaining that you should let go of your ego during training. For some people, that's really difficult. I think it's directly related to being relaxed or not also. People who really don't want to lose will have a hard time relaxing.