A > 9 hour race would really be tough. It sounds like most of the race was on the bike. I like the idea of a kayak leg instead of a swimming leg. How many ropes were set up for the rappel? I would imagine you could end up waiting there for quite a while if you arrive mid-pack.
I volunteered this year so I could get $100 off my next years entry fee. Don't know how many ropes were set up as I was at the finish but I didn't hear of any delays at the rappel. A lot of people had difficulty with cramping and being unable to walk after the Kayak portion.. Imagine after doing everything else then sitting in cold water unable to move for 2+ hours...