This is true, 555. Sometimes you can't see the dips, divots or holes hidden in the grass. I once cut across a yard at a brisk pace and trip on a mound I didn't see. I tucked and rolled as I fell. Sort of looked like an olympian as I got up, looked around to see if anyone was watching. One neighbor saw this happen. As I drove by him, I said, that's not sunburn on my face.
I wanted to see if he would put it on at some point. He did wear it on the longer runs, but not while going block to block. Next time I will insist, as I know what has occurred in the past.