Yes, at least in principle- because the "piston" doesn't have to keep stopping and starting again.

Don't think it's quite as simple as that. Ignoring the compressive and power stroke forces, the energy to accelerate a piston is returned by the piston when it pulls on the crankshaft when being decelerated.

 

There'll be losses through friction and the like, but it's not like (say) you or I trying to oscillate a piston up and down in our hand.

 

Comedy value? How do you Brits pronounce piston? (peestone?). Sure hope its not as ridiculous as "aloo-min-yum"

Meh!

I live near this place

http://en.wikipedia.org/wiki/Penistone

From first principles, the Wankel should be more efficient because of two factors:

1. Lower mass than reciprocating engines

2. Less loss of kinetic energy from frequent changes in piston direction.

This is a gross simplification, and a lot of other factors including leakage make it less efficient, but I still hope engineers will get past these limitations.