I have found that trying to use the trigger reset during high-stress shooting consistently causes me to do one of two things:
- Miss the reset by pulling the trigger short.
- "double tap" when I didn't mean to
In either a combat or SD situation your ability to feel where the trigger resets is going to be severely diminished - fine motor skills are one of the first things to go.
For target shooting, staying on the trigger reset has obvious advantages, from minimizing movement to reducing the opportunity to jerk the trigger: it helps you maintain POA/POI - somthing that you're not really going to have in a high stress situation.