Brian Zins, the 12-time National Bullseye Pistol Champion, has an article in Shooting Sports USA magazine about his trigger control. Here is the article: http://www.ssusa.org/articles/2015/10/16/zins-on-bullseye-trigger-control (http://www.ssusa.org/articles/2015/10/16/zins-on-bullseye-trigger-control). It has two elements that some may find anathema:
1. He places the first crease of the finger on the trigger, not the pad. His reason is that this part is more sensitive (to feel the trigger better) and more direct as it avoids compressing the fleshy pad before the trigger is affected.
2. He begins his trigger squeeze as the front sight is wobbling into the bullseye, not after everything is settled. His reason is that if everything is settled first, the squeeze moves the front sight slightly; but squeezing on the way in puts pressure on the gun/hand system that stabilizes the front sight.
I tried the first point this morning and found that the squeeze seems more direct, although I haven't tested it at the range. I'll run that test this Sunday.
The second point is one I've seen elsewhere - if you accept that the muzzle will wobble (within the 10-ring if you have good SHF and NPOA), beginning the trigger squeeze as the muzzle moves into the bullseye breaks the shot at the center, as opposed to beginning at the center and breaking the shot as the muzzle moves out (costing you a possible X).
This seems worthy of discussion.
I could see the second part working if you had a 2 stage trigger and worked through the first stage as things are settling. I don't think it would work well with a single stage trigger though.
Shooters who are serious about accuracy, (as apposed to those who feel 3-4 minutes is good enough)
Bury their finger on the trigger with the AR platform.
Part of his technique may be because he's shooting a handgun AND doing it one handed (Bullseye rules). You don't have so much freedom to alter your grip on the handgun to affect trigger reach without compromising your grip in other ways. Using the first crease also seems to be very common among 1911 shooters depending on their hand size just because of the design of the pistol. The reasoning behind using the crease I find interesting though. I'll have to experiment with that.
Similarly for the trigger squeeze. With only three fingers and a thumb to hold the pistol, the trigger squeeze will definitely play into the wobble and he doesn't want to be holding the pistol up for too long or else his muscles will get fatigued, so merging those two things is probbly helpful. Beginning the trigger squeeze while still wobbling is also common when shooting a rifle standing for similar reasons. Not sure I'd do it when prone, but then the wobble zone is much smaller.
There's people that shoot sub MOA with the pad. There's people that shoot sub MOA with the very tip. And there's people that shoot sub MOA with the distal joint of the index finger.
Regardless, Appleseed has never tried to teach that level of shooting.
(For what it's worth, none of the top tier competitors in smallbore or high power I've met use the joint.)
I read that for the first time a couple of months ago and have been doing it ever since. For me it works awesome! It does seem to give me better trigger feel and my groups tightened up a wee bit - not huge, but far fewer shots were off call due to my trigger squeeze. I recommend trying it!
It's easier to find chicken teeth than absolute truths. Like Agrivere posted, give it a try, you might be pleasantly surprised.
AJ
Saw a guy on my last seed that would slide his finger off the trigger after the shot broke and touch and hold for a second on the back of the trigger guard. I was gonna say something, but thought I'd see how he was shooting first. All shots in the black square. I've done it before where "correcting" someone who didn't do things Appleseed "just so" opened their groups up, so I left him alone. Check their targets before you go saying "do it this way".
In offhand, I high tight grip, accepting your wobble area, and breaking the shot moving toward center rather than away from center will bring much better results. How much finger you have on the trigger depends to certain extent on your hand size and the size of the gun.
AMU teaches that you should put your finger naturally on the trigger. that is good advice.