Total consistency. I can muddle through with RDSs, magnifiers, and LPVOs up to 8x with indifferent form, get good hits to as far as 600 yds on weird positions etc.
For real precision, for 900 yds and out, etc I found that my earpro and my glasses messed with me and I just need to practice to be absolutely repeatable. Me, for some reason, I was doing not random but two specific positions so would get parallax effects, and 25% of the time hit about 20 moa low all of a sudden. Mostly fixed it now but it took a class and someone looking at me to fix it.
Anyway, I also CANNOT take the "do not use progressive lenses" advice I get from many because there's a reason they are prescribed. I cannot see turrets, charts, levels, logbooks, etc if use distance-only glasses. That ship sailed 20 years ago.
My "outside glasses" are much bigger than normal at work glasses, so the focus bands are much larger. (They are also impact rated, and cover enough of my eyes to be plausible safety glasses as well!) That also helps a lot, and I can tell when I quickly take a shot with normal glasses that I have to be really, really on the ball to line those up or things look weird quickly.
I've generally optimized my rifle for this as well. Hard to shoot well with other people's guns sometimes. I have a fairly high scope (incidentally works better for clipons, but not mounted there for that reason), and adjusted the stock and cheek rest, etc to encourage me to use a more face-forward (head up) position. That helps optically and for repeatability, so you may need to adjust your setup. Don't forget that if on a non-adjustable gun, you can start with tape, cardboard, towels and stuff to try out LOP and cheekrest changes temporarily.