skribs
Grandmaster
I found a video that shows our hand position pretty well. He is demonstrating "our katate tori" in combination. But you can see how he grips uke's hand, leaving the wrist clear. (10 seconds to 11 seconds) You can also see how he is pulling with the pinky and pushing with the thumb. (23-25 seconds)
Is this what you mean, at the end of the combination starting at 2:23? (they are putting in a lot of extra, looks cool stuff, as this is a "kata contest." some of it is over the top fluff...)
No, that's not it.