Will only share my thoughts...no data. Just because you are drafting...why wouldn't there still be a commensurate savings in watt expenditure. Lets say there is a 40% reduction in drag by drafting...whether in a group or another rider...no doubt great economy of energy in a group. Aero still works on the bike including riding in the drops versus not.

The difference is, in a pack you are much less closer to threshold versus riding the same speed in your own air. So each of us have watts to burn and why riding a bit less aero typically isn't as problematic...riding on the hoods etc.

I have been dropped on a group ride before and probably more than a few here have as well if they have ridden with some fast guys when the speed gets way up. At those speeds, even in a group we are getting dropped because we don't have enough power to overcome aerodynamics. So fast wheels it seems to me would help then as well.