Well, here are a couple of things to chew on:
The most climbing I've ever done on a single ride was about 6300 feet (this past weekend, as a matter of fact)
Oh, and you say it was a series of out & back climbs? Well if I were on your ride, I would have likely bailed when the going got tough. :o In fact, on my ride this weekend the opportunity presented itself so I cut out the last few miles to the top of Mt. Tam. :o :o Your tenacity is really something.
So there. You're my hero now. Deal with it. :D

