Has anyone tested race wheel hubs in a controlled environment without variables (same wheels, spokes, tires, same physical testing environment) to determine if there is any definitive, measurable difference in performance?

I've been curious about this over the past few years, switching wheels many times on my bikes (Dura Ace, Zipp, Mavic, Enve, etc), just to experiment.

My Dura Ace hubs seem to be the fastest coasting of any I've owned, but I have no way to know if it's just imagination, or if there is some variable coming into play that I'm not considering.

It'd be great to see tests of hubs and bearings, to go along with the aerodynamic wheel testing and tire testing we've learned from.