Dear Former Boss:
You signed up for one of the triathlons I'm doing this year thinking (I'm sure) that you'll have an easy time beating me. After all, you did really well in the races you did last year, and I was just starting out.
If you hadn't been such a --INSERT four to five-letter-word HERE-- to work with, I might see the race as an opportunity for friendly competition between former coworkers. However, since you were a micromanaging jerk who consistently tried to get me in trouble with upper management, you'd better believe I plan to kick your butt to the curb.