It's my only way to control the size of the pool. It's true that having the rate change almost daily is different compared to other pools. At first I was a bit wary of adjusting it too often, made sure to give proper notice etc. Loosening up my own rules there has worked well in practice, though. I have realized that doing the changes without notice mostly helps drive the change I want, compared to giving notice. This might annoy some, but those who have stayed long enough realize it works both ways. I don't go drumming around the changes upwards, either. Can keep them up longer that way.