Originally Posted by
operator
Mechanical efficiency with more teeth? Sorry, that doesn't make sense. If anything, the longer your chain the less efficient it is.
The bigger your cogs/chainrings the longer they will last.
Even if more a few more teeth (but with the same ratio) is more efficient in some way (less friction?), the effect of adding a few teeth to your chainring and cog would be so minor that it would be basically irrelevant.