makes a big difference when you do not have the layers on. Even if there are no hills. The rides I have been on lately with groups amaze me. All of them wearing all these layers and me.... keeping it simple. I think that is the key with the wind (I would say this only when it is warm out). I like watching the guys with wind breakers with the wind. The wind blows their jackets up like a marshmallow and it drags them. Sorta funny really.