Pucker factor is all ways a consideration. Until you are in the situation you will never know how you will react. It takes your training time to kick in when you are in your first gunfight.
Recently there was a post involving a shoot out between a Police Officer and a robber. The Officer fired some 20 rounds before his training took over and he remember to use his front sight. These two officers did some what better.
That said I think Kraigway's first posting is spot on.