Ron,
You aren't getting many answers here so I'll take a shot at it.
I believe that the little finger trigger is "counter effective". By that I mean that many times things are included that may or may not be of use. Someone, somewhere thought it would be a good idea and maybe somewhere it works for someone.
I feel that if you use that, the tendency would be to apply pressure on the "trigger" which will lead to tension in the hand that we try hard to reduce. If you have as relaxed a hand as possible, then using the little finger to "grip" that thing will only put more tension in the hand. And MAY very well tend to apply a downward/foreward rotation to the release.
The NTS likes to have that finger and the thumb hanging essentially relaxed.
It is a little like the plate found on some metal based tabs that SOME think is a thumb rest. It is not. It is for placing under the jaw for the low target style anchor. If you use side of face for an anchor, that gets removed too.
Arne