ceadmin:
Just always have. Always seem to be plenty of smaller gills. Not all of us do this, but I do and it hasn't seemed to hurt anything. We don't catch tons of smaller fish, but we seldom (in summer, anyway) fish live bait. Mostly just jigs, Road Runners, BeetleSpins, etc. I figure if I'm catching any 3" gills on artificials, there's plenty of them to go around.
In winter, with waxies, I'll usually throw the lil ones back.
In my own ponds, I won't bother doing this until at least next summer (3rd year). I've been catching a few tiny ones (2" or so) but figured they are the just the ones we tossed in from IDNR last fall. They were almost fry-sized, back then.
In a lifetime, the average driver will honk 15,250 times. My wife figures I'm due to die any day now...