To do good at shooting multiple targets, you need to practice shooting multiple targets. And you need to practice it more frequently than I have this summer . . .
I shot a USPSA Special Classifer match this morning and blew two stages because I went too fast. Trigger jerk and poor follow-through were probably the cause of my problems. I hadn't done much practice on multiple targets the last few months, and I noticed that I just didn't feel smooth at the beginning of the match today.
You can only learn from experience if you pay attention!