My sisters horse Renegade is retiring too. (He's actually a friend's horse, but Sam rides him the most) He didn't show like Snoopy did, but he did teach alot of riders how to ride, and he was still going strong at age 34. However, it is the best decision to retire him. :)
Very nice story. It is true though that the horse will tell you when it is time to retire! Plus trail riding can be just as exciting as going in a dressage show. Have fun with Snoopy!