This is perception, so I may be all wet here, but... the 12 gauge is the yardstick I use to measure lethality. Most birds I shoot at with the 12 expire fairly quickly and are "brought to bag". With the 20s and 28s I've owned and used, I noticed what I believe to be a definite loss of lethality. Birds that would likely have died if I'd been using a 12, end up being lost and likely wounded with little chance of surviving. The 16 seems to hit a truely "sweet" spot, balancing very good lethality and a much better weight and balance than most 12s can deliver.
