Let me preface this by saying that I am NOT crapping on lasers, but I've watched dozens of people center the sparkle and then shoot 12" away from the X.
Aiming is certainly important, but getting the shot off without any of the 100 different causes that result in a miss is the name of the game. I've been shooting roughly 75% weak handed lately (Had shoulder surgery last year and just fell out of the practice) and found myself contracting all of my fingers on trigger press, sending everything uniformly to the right. With a few adjustments and a couple hundred rounds, I managed to scoot everything to the left and into the black at 7 yards. Of course there are fliers, but I would have them if I had the gun in a vise and a 21' barrel, because it has been ordained that my prescribed level of "suck" shall not be infringed. This is one more reason why I consider golf and handgunning parallel Hells. You fix one microscopic flaw and initiate 7 new ones!