Originally Posted by
kbarch
No.
There are a number of ways energy can be expended on the bike without getting it to the wheel. The most extreme example maybe something like jumping up and down while doing a track stand. I'm sure you can imagine a number of other ways our feet can apply force to the pedal where the resistance comes from the structure of the divetrain itself rather than the road or the air. I'd suggest that rollers are inherently unforgiving of the kind of pedaling form that wastes energy and upsets equilibrium that way.
I don't know anything about the absolute magnitude of the energy losses inherent in poor form, but riding rollers teaches one that they are not negligible.
Not a stretch at all, and it is quantifiable. You used a rather silly example, but in the real world, any force applied to the pedal which is not at right angles to the crankarm is wasted in proportion to the vector analysis of said force. Hence "pedaling circles," which doesn't mean pulling up on the backstroke but rather to applying force normal to the crankarm. Which is not really very simple, takes a lot of practice, and rollers do encourage such practice.
It is quantifiable by some pedal-based powermeters.