Originally Posted by
rmfnla
Hydraulics make sense for brakes because of its power multiplicative effect, something not applicable to shifting.
Another answer to a question nobody asked...

If I had disk brakes (which I don't foresee) I think I'd prefer hydraulic brakes, but for shifting, I don't see the point. I do like the idea of the eTap -- and not just because I already use SRAM. In spite of the multiple batteries, eliminating the wiring just seems a lot simpler and easier to install. The shift method would take about one ride to get used to -- no more than the SRAM double tap did.