Have you ever used an electric assist? a 50Wh battery weighs very little[1], the motors are similarly light, even by road-bike standards. Remember that there is a minimum weight, so you have a small amount of deadweight to play around with as well.
That would give a pro biker a 10%[2] increase in power usable over 1 hour of the stage. It would make the uphill parts way better while negligibly affecting flat terrain and downhill.
1: Maybe 300g for such a battery were it lithium polymer. Lithium primary cells can be even lighter.
Ive some of these tube-size assists are 100 watts. That could be as much 30% in sustained riding.
They were designed to provide half the power for commuters.
That would give a pro biker a 10%[2] increase in power usable over 1 hour of the stage. It would make the uphill parts way better while negligibly affecting flat terrain and downhill.
1: Maybe 300g for such a battery were it lithium polymer. Lithium primary cells can be even lighter.
2: Or 5% increase in power for 2h, &ct.