@lowlight - thanks Frank...I really enjoyed this one and as I posted in the other thread, I really like these bite sized length and single topic vids and hope you and Chris will continue to produce them.
Wow, grip and placement on the trigger shoe has been a long standing issue for me with the JAE chassis I shoot (but I'm also looking at getting a Vision for a number of reasons, but ability to change grip config is a principal one).
I too have small hands (hey, we aren't small...we are just efficient). Wrt to the JAE, I worked with Tyler Kemp to produce a 3D printed modified grip that is far more vertical than the OG one and has the grip front strap closer to the trigger shoe. Its better...not sure its optimal but its much better.
I don't know what's going on with handgun grips, as you mentioned. But, I have seen an evolution in competition shotgun stock fitting and in particular with the grips which have generally gone from really slanted back, traditional hunting stock type, grips to ones that are far more vertical and closer. Of course, in shotgunning the trigger control is far less important that in rifle.
And I found it very interesting that you mentioned finding an "index" for your hand placement as I have spent a good bit of time (and confusion) trying different hand positions and looking at the impact on my trigger finger and keeping it parallel to the rifle for a straight back press, and looking for a reference (index) so that I can get back into the exact same position after running the bolt. I'm still working on it and I'm looking forward to some professional eyes on my fundamentals in PA in Sep.
Now, what Chris showed with the AI and middle finger prob wouldn't work for me (or perhaps you) because of hand size. Chris looks like he could palm a basketball! haha
Final note, when teaching skeet, if a student had a consistent issue with a particular target (like H2 for a right-hander) and was making the very same error each and every time, we often would have them use their middle (bird) finger on the trigger. This makes the shooter a bit uncomfortable so their focus on the target is sharper and it seems to work to get around bad muscle memory of the erroneous move. Unfortunately, often as soon as the student becomes comfortable shooting with their middle finger, the errors come back.
Cheers