Using that formula at 6'3" 189 I'm on his borderline avoid hills list. For what purpose? He's a coach, and his books are about being a competitive cyclist. Sure, if I want to be competitive, it makes no sense to race 145 pound riders on courses with significant climbing.
It's been a while since I picked up one of his books, but IIRC he said something along the lines of if you just want to go out and ride your bike, this isn't for you.

Again if competing, the sit stand decision has a lot of considerations. Otherwise, go with what feels best.

​​​​