While watching a vid on youtube some time back of a unit conducting live firing, i realised that the shooting was all in double taps. I couldnt tell if it was one person doing it, or everyone was shooting double taps as SOP. Anyway it then got me wondering; just how useful are double taps? If you fire two shots per target, you effectivly halve the number of targets you can engage with one mag. On the other hand, if someone is worth shooting once, you may as well shoot them again? Discuss?