I don't recall having to deal with that to any degree. I'm normally juggling several things at once with my writing, and if I get hung up on one, I just shift to another and keep going. But usually I'll just keep stumbling ahead until things pick up again. If all else fails, I'll jump into one of my kayaks and go wave jumping. Having mother nature coming at me over the bow usually washes away any writer's block, if it was there to begin with.