Yes, every 20-25hrs is about perfect for your average homeowner. Any more just makes a mess, which you don't want on a belt driven mower deck. I've been using Supertech general purpose lithium grease on my Cub Cadet 2544. 4yrs/125hrs and everything spins like new.
Amsoil Water Resistant Grease at about 50 hours between a couple of pumps. The stuff stays in place and protects them pretty well. Red and Tacky does ok, but I hate working with it because it's so darn stringy