Man, at the last worlds I noticed a crowd of "spies" behind me.
It took me a couple of breaths to recompose, because unexpectedly I felt a rising in pressure... being observed
I'm not immune to erros, so I do what I can to avoid them.
I block my index finger with my thumb, and when positioning the hand for shooting I touch the trigger guard with the side of my thumb, but that's it. After positioning, all done mechanically, the hand just goes off a little bit away from the trigger guard. Then, I know I'm ready to shoot when the condition presents.
Through the years I developed a mental trigger... readiness, condition, aiming, double check, aiming, action (firing). This way I can't go off, because a series of procedures have to be done before releasing. I just can't release in between, my brain is occupied with the sequence, so no other order can enter.
This sequence has to learned step by step, as a voluntary procedure, until it becomes automatic. Of course, from time to time, I practice just the sequence, to maintain the automatic level.
A very special warning here...
You have to know what you are doing, and being aware of middle road shortcuts, and worse, middle road "secondary effects". The must feared one is the potential developing of target panic. Again, consider yourself warned.
Target panic is a mental shortcut development, that will drive you nuts, leading to demotivation and going out of shooting. Why? Because target panic is an automatic brain trigger that will release every time you see the target center, or, when approaching it. You can't do anything against, it's a nightmare.
This is archery definition of it:
"Target panic is essentially an archer's worst nightmare. It's defined as anxiety when your pin is on target and can manifest itself in many different ways, including hovering your pin above or below your target, smacking the trigger right when your pin gets on target, or flinching when releasing an arrow".
Don't let anyone tell you differently, target panic DO affect rifle shooting. Sometimes very subtle. Have you ever saw an index finger being nervous on trigger blade? That's the beginning.
Target panic is very evident on prone shooters, less so on benchrest, but it will avoid you to wait for the condition and to shoot when you're ready.
The best benchrest solution to avoid it, but I don't like, neither recommend the technique, is aiming and then rising your head and shooting when a condition presents, not looking through the scope.
This could be another very interesting subject to discuss...