In years past I was a very serious dove hunter. I once read an article or comment from another very successful Dove Hunter who advocated using 1 1/4 oz. of number 9s to fill out the pattern at longer ranges, saying there was enough of them in the pattern at distance to provide multiple strikes, and put a dove down.
Just for the heck of it, one late season hunting over a picked corn field, I gave it a try at 1220-1225. I didn't lose any even at 30 to 40 yards, or have any hit but Fly Away. I saw no advantage or disadvantage over my standard late season load of 7 1/2 and 1 oz or 1 1/8. I see no need to try it again. Although they worked that day for me, I feel much more confident and efficient using 7 1/2 and no heavier than 1 oz. or 1 1/8 at most. Most of my dove, regardless of range or point in the season, were taken with 1 oz. or 7/8 oz. out of a 16 or 20 bore.
It was a fun day just for the novelty of it, also partly because I was using a Super X Model 1 factory choked .009 that made absolutely beautiful, efficient, patterns. I was not undergunned even at 40 yards.
I'm surprised Winchester would even offer that load. They couldn't have consulted too many dove hunters first. Blended shot, super fast, heavy load? No need for that new mouse trap. Is it a current market offering? Even so, you won't be seeing them around long. "Consumer (demand ) is King".