--Efficiency studies on the Toyota Prius claim that it delivers 32% of energy from the gasoline it consumes to the road compared to only 16% for a conventional gasoline engine. --
We are not talking about the gasoline engine. We are discussing regenerative braking.
--The efficiency of the charging cycle for a battery connected to a wall charger may be 85%. That is your best case. After you subtract the losses in the drive train and efficiency of the generator, those losses are added on top of the 15% inefficiency of the battery charging process. You're still throwing away more than half the kinetic energy of the moving vehicle to bring it to a stop.--
You reference nothing to get to your losses. I would expect that we are recovering more than half. Still, even recovering half is much, much better than recovering ZERO.
The hybrid still has rotors and/or drums. The amount of regenerative recapture is dependent on how much isn't expended as friction/heat in the conventional part of the braking system.
Rather than try to assert a negative, why don't you produce statistics show just how much you actually recover? Anything you do manage to put back into the battery will still experience losses again on the way out of the battery, down the drive train and down to the wheels. Is it really a paying proposition?