Richard Lee Byers
I'm not too troubled by it. I think that's because I've trained myself to put my butt in the chair in front of the computer and work on a regular schedule. Discipline and routine train your brain to produce as required.
That's not to say I never get stuck when trying to come up with a new story idea or figure out exactly what should happen next in the story I'm working on. But I'm not often in the situation of knowing what should happen but not being able to make the words come. Which seems to be what many people mean by writer's block.