Could be. I seem to see a low left when I fluff the launch. As you say the trigger release seems critical. I have to sit on second stage and make sure there is a direct to the bore movement of the pad of the finger. Also lung empty seems to work better and keeping eye off scope rubber as well. Shooting in a hat looks like a no no using the deben as the peak hits the Ir turret on recoil.
BFTA/NSRA County Coach
CSFTA Chairman/BFTA Rep