Once you have learned to pressure flake, the task on control begins.
This group of photos demonstrates how I do it correctly and then intentionally incorrectly.
I beleive over shot is a diving of a flake as it in encounters mass. To reduce the effects of this I remove mass on the terminal end of the flake first. I have indicated this area with a circle. I will remove the circle first with a "half force" then the flake from the opposite side.