I don't have that problem with a twist shifter for my commuter's 7 speed hub. Also I can forget about handling a water bottle 15 minutes into a ride at the temperatures where mittens are needed. Same goes for drinking coffee mug while riding in the morning, it freezes before I can finish, so I just wait til I get to work for my morning coffee.

My current mittens worked OK until about+5F, below that temp. my thumb and a couple fingertips got unpleasantly cold. Insulated gloves don't cut it at all below +20F for me. I don't mind spending the money to get a product that will keep my ride pleasant under the most severe conditions.