[jonathantm]

Electic shifting is irrelevant here. Does it contribute energy to the propulsion? No. It would be akin to asking if wearing a digital watch rather than an automatic (mechanical) watch makes your bike an electic bike.

You can say it aids propulsion, but that's only because it aids managing the gear ratios. It doesn't contribute energy to the the propulsive force of the engine of the bike (the cyclist). Yes, it is involved in the drivetrain, but the engine in the derailleur does not contribute wattage to the turning of the cranks. It's power is applied to a horizontal repositing of the conduit through which the propulsive power is transferred.

[mmariani]

Technically you're correct. However, practically there is an advantage of electric vs mechanical shifting. Usually mechanical derailleurs misbehave a little when used under load. When in turn electric derailleurs shift just fine. That's one reason why all pro sprinters ride di2, eps or etap.