I was out of the gate fairly fast and estimate there were maybe 50 runners ahead of me at the bottom of the W's. I don't waste any time on my walk and generally am able to keep up with most of those running. One thing I notice is the runners slow down considerably when they stop running and I pass them only to have them huff past me again repeated until they can't any longer. I train walking 4+ mph at 15% grade on my treadmill. I blew up in Leadville last weekend at mile 60 and was able to mostly walk it back 40 miles at a good clip, I believe because I practice walking.