Re: Jamming a technique
Uke should always be "resisting" to a sempai with neither ego nor a point to prove ( that the nage's showing some weakness or flaws). When training with kohai, uke should gauge the ability level of kohai as nage,give correct amount of resistance to help kohai along.
When doing demo or with sensei during class instructionals, uke should just flow along with maximum 30% resistance.
I personally like the moving through molasses quote. Thanks Eric It is as internal (yin) as aikido can be for me.