One of the facinating things I see in Aikido demos is the ability of the defender to, when grabbed by the wrists, to create pain in the attacker and control them (usually bringing them to their toes)through a slight turn of the defenders wrist. I don't know if this is a re-alignment of the attackers joints thereby locking them or pressure on a point. Any insights would be welcomed.
Are you sure what you watched were aikido? Sound more like traditional jujitsu or shorinji kempo to me.