Originally Posted by
Machka
Why "stay away from your back brake in the rain"?
It is okay to use your rear brake, judiciously, when it's wet.
Here is some great info on braking technique from Sheldon Brown that you may want to check out.
If you sit up, don't you provide some extra wind resistance which can slow you down a bit?
Of course, but the stability gained by being in the drops far outweighs whatever benefit you're going to get with wind resistance. You can open up your arms and legs and even sit up a bit while in the drops to increase wind resistance.
I hit 51 km/h on a descent today.
But it was a very straight descent, on a nice dry sunny day, on a good road.
Every little bit helps, I suppose.