Originally Posted by
rubiksoval
Pros don't race 1x. One team catastrophically tried to a couple of years back. They lost multiple races because of it.
No teams try to use it now.
Mads Pederson rode 1x by choice in the Belgian spring classics in 2019.
When he won the Worlds in Yorkshire in the Autumn he was back on 2x, and he's been riding 2x in general this season as far as I can make out.
1x makes sense for some applications. I don't know why anyone would even want a front derailleur for a dead flat race like Roubaix. Just leave it in the 53 all day, and you're never going to go lower than a 19 at the back anyway.