A quote from "the Bean". "I say, if building codes dropped the reference to controlling air temperatures and switched the requirements to controlling mean radiant temperature, building performance specifications would have to change overnight. Bad buildings have low MRT’s in winter and high MRT’s in summer; this contributes to large differences in the vertical air temperature; creates excessive drafts and increased radiant asymmetry. Bad buildings also have uncomfortable floor temperatures and are challenged to maintain reasonable levels of humidity." Bean, R., The Big Picture, Beyond the Benchmarks: Better Buildings, August 2011 He is dead on. If you can hit a MRT of 65-68* you will be fully as comfortable there, probably more so, as in a house with a MRT in the 50's and an air temp of 72+.