As others have said...it depends. If my speed is holding up traffic, I'll stay out of the way as well as I can, considering the conditions of the road and how they affect my safety. If my speed is faster than traffic, I'll take the whole road.
Here's an example from my ride last weekend, on a road that is twisty enough where decently-skilled cyclists are significantly faster than cars...
Earlier on this descent, I had one motorcycle pass me and one car move out of my way. It was a lovely day with more cyclists on the hill than cars
