To be totally fair I watched it again this morning, and I may have overstated when I said that he implied less penetration per pellet with the .410. That was not explicitly stated, and in my defense of the .410 on small game birds I may have put words in his mouth in my previous statement. Others can decide when they watch it.
What is more than obvious tho', is the unfair comparison between a "Spanish, or French" loaded .410 load which probably contained soft, cheap shot with no shotcup (notice where the basewad had pellets embedded in it and penetrated the cardboard at 40 yards. This is an indication of a cheap load) with a Black Gold Gamebore 12 ga. load of impeccable quality, which has hard shot and a full shotcup with petals (you can clearly see the shotcup on the video). He states at the end that this was only a layman's test, but in order to maintain any credibility he should have at least used a high quality load for the .410, if he was going to do so with the 12. To not do so could be construed as having an agenda against the .410.
Nobody in their right mind shoots game with a .410 at 55 yards, so that was really pointless, IMO. But, the pattern he showed from the .410 at 30 yards was not very good, and a clear indication of an inferior load. If he were to do this again he should state the chokes in each gun, and use high quality .410 loads, like the WW 3/4 oz. load that I shot this pattern with, with only .008" choke.
When you put out a video that is watched around the world, and begin by stating the inefficiency of the 1/2 oz. load on grouse, and state that it should never be a beginner's gun, you forget about the thousands of dove shooters for whom a .410 is entirely capable, even in the hands of a youngster. I'll agree the 28 may be better, but my 8 yr. old grandson killed 7 doves, on the wing, with a .410 on the first dove shoot I ever allowed him to shoot on, and he's no phenomenon, he was just coached carefully.
SRH