From what I understand, the painless nikyo works this way:
once you get to hold of uke's hand, you then hold onto his upper arm in classic nikyo position.
But instead of lowering uke's forearm and thereby twisting his wrist, you maintain your hold on uke's arm and take a step back.
Uke's is pulled forward and down by your movement and when he or she attempt to stand up, you allow uke's forearm and elbow to rise up.
If you maintain a tight hold on uke's hand, uke will run right into the nikyo, "activating" the lock.
Anyone else do this this way?