Originally Posted by
kingston
The only things that matter are range and spacing. I couldn't care less about the number of gears that overlap across the rings.
The 3x9 setup has a slight range advantage over the 2x12 setup, giving you 2 extra gears at the bottom, and 1 less gear at the top. But, the average step size of the 3x9 setup is 15%, whereas the average step size of the 2x12 setup is 12%, giving the spacing advantage to the 2x12.
It's like saying 3 is bigger than 2.
3 is bigger than 2.