It occurs to me that my proposal is rather selfish, actually: motivated by difficulty for a relative outsider (I don't follow very many WGs) in understanding the actual proposal. I'd have read a fair bit of datatracker records and mailing list archive content to begin to understand some reassignment proposals, and/or talk to a number of people. The flip side is that infrequent mass reassignments must seem like a lot less work to the IESG. Each lone reassignment would have to be guaranteed to be real cheap, or the concept won't fly. But we are also not fond of light-weight processes here.
Given this, I think I will now butt-out, even if the IESG and IETF end up adopting something like my suggestion.