Originally Posted by jemoryl
I don't think it was FSA, since they do a pretty good business in flogging off overpriced parts with ceramic bearings. The story you have in mind might be from a smallish wheelbuilder (maybe Rolf or HED? Certainly not Zipp!).
ah, you're right, it was HED. I found it
http://www.hedcycling.com/wheels/ceramicbearings.php
"
There was a measurable drag difference between ceramic bearings and steel bearings when we tested unloaded wheels, but the difference was small enough that we could not measure it on a loaded wheel."