I think most organized rides try to have a rest/sag/aid stop every 20 miles or so... 10 miles is very unusual... I also stop if for nothing else, because I "paid" for the pleasure and we call it "shopping" - sometimes there are really good freebies and I want my share... if not I move on. I've done a number of centuries and a couple of double metrics. Some times I feel really good and keep moving. Sometimes I need and in fact, ride but for the next stop... it's the only thing keeping me going. No rules, hard and fast, other than have your own plan, acknowledge it can change once you start to peddle and you assess how you are feeling and depending on the ride... some rides are "festivals" some are not. I would not sign up for a festival type ride if I just planned to race through the event.

Fastest century (total time - I don't split resting and riding time) was 7hr. 25 minutes (AMTRAK). Slowest was Cool Breeze, almost 11 hours. I was leading 4 newbies through their first century. Good gosh, never again. That is a long time to be out on a bike and on a saddle - and every rest stop was torture for me... like herding cats... average 30 - 40 minutes before i could get everyone back on their bikes. Lunch I recall was over an hour... painful!