Depending on who you listen too, there are seven or eight or nine marksmanship fundamentals They will make you shoot beter, but there are only two that are marksmanship essentials, sight alignment and trigger press. Sight alignment is far more important to making good hits on target than sight picture. Why? Because you can hit a target without seeing the sights at all such as a contact shot or shooting from retention position. Trigger press is nothing more than breaking the shot without moving the sights.
With aimed shooting, we must see the sights on the target. There is a natural “wobble zone” which occurs, resulting in the tracking of the sights back and forth across the target. Your heartbeat causes a pulse as the blood moves through your body resulting in very small movements even in the most stable positions. With the pistol, wobble it is much more noticeable especially when shooting one-handed. By relaxing and building a good grip and a stable stance, we can minimize our “wobble zone,” but we cannot completely eliminate it. We have to accept and ignore it.
In this video, Tom Givens explains managing the “wobble zone” with iron sights.
Even though it doesn’t always appear that way to your eye, your “wobbles” don’t effect sights alignment significantly. Your sight picture is a mess, but you will still hit your target. Try this, with an unloaded gun, and aim at a spot on the wall and get a good sight picture. Keeping your gun in place, shift your head a few inches to one side. Your sight picture is bad, but because your gun is still pointed on target, if you broke the shot, you would hit the target. Wobble is a similar effect, but reversed. Your head is staying still, but your gun is moving a little. The sights are still in alignment and even though the entire gun is moving a fraction of an inch, the front sight and rear sight are moving together. The sights may not be in line with your eye at all times when the gun is wobbling, but they are in line with each other and with the target.
Ignore the optical illusion and break the shot. Your shooting will improve.