Hi Skeet.....
I'm not arguing with anyone. If you can teach someone easily with a 28 or 20 and they can master the firearm and be satisfied, then you've done your job. My wife shot with us at hunter ed class we were teaching and was very very frustrated till one of our instructors brought over a gun he had cut the stock on which fit her much better, a 20 ga. in this case. This was an over-under and heavier than the guns she had been shooting prior, but nonetheless much easier for her learn how to lead and shoot. In fact, her getting a double with it, really got her enthused.
Subsequently another bird hunter friend of mine had her shooting with a 12ga one time when they were down at the skeet range. That was also cut down for kids and women. He loaded up some lo base brass and 7/8 and 1 oz loads for her. These proved to be no problems for her whatsoever. As for shooting loads heavier loads by accident or otherwise, EVERYONE should know what the heck they are shooting, and if you're teaching them and they don't, why not and why are you there?
I'm not a bird hunter really, and don't know much about this stuff, but I teach people how to shoot my muzzleloader shotgun and that gun is about as recoiless as you'll find anywhere... White 6 groove straight rifled 12 ga. When they go to a "real" shotgun, they are very prepared and find them to be a piece of cake.
Aloha...
