Originally Posted by
nfmisso
Yes, because there is less bending of the chain. I am not sure that it is practical to measure the efficiency difference; it is very small, in the noise compared to different lubrication choices for the chain.
I agree that the difference is negligible for real world use, just like any weight savings from smaller chainrings. I just don't understand the popularity of compact cranksets. Do people just prefer lower gearing overall?