I’ve taught this warm-up exercise to a few students, all of whom enjoyed the challenge, although I’m not sure it became part of their practise routines. I wish it was part of mine, but I always go straight to paradiddles…
I’ve notated it below for anyone who’d like to try it for themselves, or give to one of their students to try. The most challenging aspect is accurately counting the diminishing bar lengths. As you progress through the exercise, it feels like it’s getting quicker. Of course, the tempo is fixed but the bars are getting shorter. An especially tricky bit occurs when you get to the start of the fourth line and have to count 2, 1, 2. Anyway, I hope you have as much fun (!) as Erskine does with the Peter Erskine Warm-up exercise.