Interesting that you wrote about a 12-15 seconds difference in pace for every 1% uphill. I wrote 12 seconds on my response above yours. In that response, I had written 15 seconds because of my personal obersvations, but I changed it to 12 seconds to be conservative. I recognized on a treadmill long ago that at pace slower than 9 mph I had a change in pace equivalency by about 15 seconds per mile, but at speeds faster than 9 mph I had 12-second equivalencies, especially in the 10-12 mph range. Tom S.