At this match, the penalty for a D hit is plus 3 seconds. The penalty for a miss plus 5 seconds and the penalty for a no shoot is 7 seconds. Those are by far and away the stiffest penalties in any scoring system out there. So you have to consider that if you aren't 100% certain that you shoot all C's or better you have 3 seconds to make up that potential D hit with a C or better. 3 seconds is a long time in terms of shooting.
The targets are scored on the best 2, 3, 5, 6 hits depending on how many hits are required per target. Typically it is the two best hits in USPSA, and IPDA. Since we are spatially challenged indoors we shoot more or less times at some targets.
Here is what I did on that swinging target. Not to say its right or wrong. I followed the target with my sights. I also put an extra round in each target because it was very difficult to call and A/B/C zone hit with 100% certainty on that small target on the move. Plus I had an extra 3 rounds in the gun at that time. Those extra 3 shots cost me roughly .2 seconds each plus another .3 seconds for a slide lock reload rather than a standard leave one in the pipe reload. So I gave up roughly .9 seconds to potentially save 3 seconds for a D hit. It turned out that I had two D hits out of my 9 total shots so the extra 3 shots potentially saved me 6 seconds.
If i was shooting a 6 shot gun I would have aimed much harder and shot only six times while making damn sure each shot was a C or better. If that target had been much faster I would have either ambushed it at the point where it stops and heads the other direction or waited for it to come into my sights and break the shot and repeat as it came back. You typically can't "double tap" a mover with any degree of success.