The art of disappearing

First session today was some basic 肩取 (Kata-Tori) techniques. Second session was katate-tori ryote-mochi. The hardest technique is a nikyo ping which requires that you completely give up your arm (your uke has both hands around your wrist) and then 'disappear' by sliding up next to uke and suddenly coming up against his wrists with almost a flick of your hand. It is very effective if you can get it. Needless to say, I think it'll take a while before I can get anything like it...