I deliberately take duplicates, because you can never tell if people will blink. That's saved many photos for me. When things happen really quickly often it's just shoot away, obviously not like a madman, but still more than you'll show the customer. I also don't limit numbers, I just aim to show them around 300-350 max.
That's why I take duplicates as well, especially if I'm taking pics of groups. People blink and if you only take one shot of a group then you may end up having to throw it out, and they won't get that picture. Anyway, I'd put the #2's on disc just in case. If you need them later then they'll probably be there, but if the disc gets screwed up then it's not a big deal because they weren't that great anyway.


