Idk about symmetrical problems, but i know for sure that tori and uke have different masses. Many complex openers don't work in mp when u try to do them using "uke".
When you play online you have 4 possibilities: Tori right/left side and Uke right/left side; some openers you made may work only in 1 case. That's why impro is better lol.


@thomas: i edited first turn too. If u contract abs in the second turn the kick will be lower.