Originally Posted by
PaulRivers
2x is just awkward. I have a bike with it, you have to shift the front ring a lot more than you do with 3x. I think it was done because racers wanted to drop a few grams and marketing wanted to change for the sake of change that makes some feel they need to buy buy new bikes. It's not better unless a few grams makes a big difference for you.
2x is fine if you are strong enough to push the big ring 90% of the time. I can't manage with a 50t but have found that I'm ok with 46t..