Notes
Ran the hilly loop from stoplight all the way around to stoplight, same direction both times. First lap, just set out to run comfortably, and that worked. On the 2nd lap, ran hills a little more "assertively", not hard but a little harder, and definitely tried to open up and go faster in the last mile once hills were done.
On the downhills towards the end, I could feel the left foot starting to slap, get sore just in front of the heel again. WTF?