It does work. Don't hang them by their legs (though aspiration worries are unfounded there, too, as the bird will always crane its face up, and people don't drown when we're upside down either). Fold his feet to his chest, and carry him belly up like a football in front of his pals. Once he's no longer fighting and has calmed down, give him a treat and set him on the ground.
I haven't seen any evidence of ratios causing human aggression. Nip anything like human aggression in the bud as soon as he gets uppity. Don't wait for him to flog. If he gives you any aggressive body language, chase him down, flip him over and carry him around. I've never had a rooster take more than three times to cure (that record was a Wyandotte who had been pretty poorly socialized and not treated well by prior owners).
Do keep your eyes out for easy guys. Lots of people are loathe to cull perfectly good roosters. Temperament is partially genetic, so don't breed legitimately awful roosters. Many grow out of foul temperaments or poor treatment of ladies once they're out of the crazy teenaged phase, but why take chances?
Keep one at a time in with your girls and see how he does. Keep the best one after you've cycled through them all, but always keep your eyes out for a better boy.