Good Topic.
I'm a big believer in 7/8ths and 1.0 oz. loads for double guns for Skeet and Double-Gun Sporting Clays. For most other sports however, the 1 1/8 oz. load does have the advantage of simply more pellets. There is no getting away from it.
If you want to be on the top podium, in Trap and 12 gauge Skeet, the 1 1/8 oz. loads have been the ones to use. I don't know if there has ever been an ATA Grand Champion or NSSA World Champion (in 12 gauge), that has used a 1.0 oz. load or smaller.
Part of it is clearly tradition or inertia on the part of the shooters themselves. I don't doubt the math discussed above, but the empirical evidence would indicate that something other than math is at play in all of those championships being won with 1 1/8 oz. loads.
Personally, I'm not shooting for a podium position any more and the advantages, to me, of the 1.0 oz and smaller loads is very real in terms of recoil.
The International shooters obviously do very well with the lighter charges, but usually at high velocity, which somewhat negates the recoil benefit.
I'm surprised that no one mentioned the many 1.0 oz. and lighter offerings of B&P. I've been very pleased with several of their shells.
