December 22, 2011 2:25 PM EST
I fast travel when its necessary, like I'm at 299/300 and I'm in the middle of nowhere. But I will always fast travel back to where I was and continue down the road.
I've completed the Thieves Guild and Dark Brotherhood quest lines and I'm working through the main quest right now. I've made a rule for myself with the main quest, that I won't fast travel at all. I'm more likely to encounter dragons and it's really making the whole experience more immersive.