How long does your wheel/hub spin for?

dat's the truth......

and bearing drag (mostly seal drag really) on a bike is around a watt IRRC, so improving it a million percent is not something you should waste much time and money on. The seals are there for a reason.....

yeah there is seal drag, but combine everything, even the work required to flex the chain. And on a geared bike, even more so.
Also under load they'll behave differently, and then there is temperature!