This article from Officer.com talks about the benefits and downsides to using IPSC and IDPA competition as training for Police Officers. I think a person who competes in IPSC and IDPA is going to do better in a gunfight than someone who does not. I think his points in regards to the downsides seem reasonable, but you can’t really practice real gunfighting. Competing in practical shooting sports isn’t perfect, but it helps. Ultimately, I agree with the conclusion:
Are you afraid that your shooting isn’t up to snuff? Well, you’re probably right – the average competitive shooter is a better shooter than the average cop. But you know something? They already know that! A friendlier, more supportive bunch of people you’ll never find. So swallow your pride and get to it!
That advice goes for people with concealed carry licenses too.