Thursday I did W7R1 and hated it. This morning I did W7R2 exactly the same run - same 25 minutes, same route, same exact distance, and I felt good all the way. What was the difference? Well, aside from much nicer weather today, the only difference was that today I kept the same slow, steady pace throughout the run. Thursday I didn't - I ran much too fast in the beginning. I think I've learned my lesson now.