I do it about once a day, sometimes on my own, sometimes with my lady. 10 times would be too much for me lol, but if you are enjoying it, go for ya life!
9 times a day is okay, but 10 is over the top. If you do it 9 times per day, that is once every 2.6667 hours, or more than 2.5 hours between jam sessions. 10 times a day would be once every 2.4000 hours, less than 2.5 hours between sessions, which is just unacceptable. If you keep this in mind and make sure you have more than 2.5 hours between sessions, you will always have a nice full head of hair. I, on the other hand, am completely bald.