It seems to me like it's the future in roadracing. Once they achieve the reliability I don't see what'sto stop it. I understand the servos and batteries don't weigh much more than the cables/housing and Ergo mechanisms inside the lever they're replacing. You can install the button shifters on a couple of different locations on the bars so shifting is a touch away no matter where your hands are on the bar.
Weight can be compensated other ways as well. The Saeco Cdales had to have weight added to them during the Tour b/c they were under the UCI minimum. I'm sure other makers can build bikes this light too. If the electric shifting makes up that "extra" weight to get the bike back to the UCI minimum then it would be well used.
The day's not far when the pro bike has electric shifting and maybe even a disc brake up front. Far, far away from the Super Record stuff we both love but racing always pushes the envelope.
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“Life is not one damned thing after another. Life is one damned thing over and over.”
Edna St. Vincent Millay