Ah. Yes, I noticed that in some of the examples.
Just to be clear about what I meant: I don't worry too much about either exact placement on uke's hand/forearm or the body part that nage uses to accomplish the turnover. If the body is in the right place it doesn't matter, and if it's not, manipulating uke's hand won't help.
That is another interesting point - small hand fold/return demands some sort of wrist maneuver. Playing terminology boy here but if you are manipulating the forearm we Shodokan types call it a Hiji waza or elbow manipulation - which includes the fabled ikkyo.
I think you can bring someone down in a kotegeishi-esque maneuver on the forearm but you are dealing with an entirely different joint.