Well, to make a long story short, I did manage to break my two-year-old PR by almost three minutes: 4:14:20. So I didn't break four hours like I wanted, but I really can't be unhappy about a new PR and also about being back in the four hours range after last year. The course was absolutely gorgeous and the weather was perfect.
I'm working on the full report so I will post that soon. Thanks to everyone for your many good wishes and support--it means the world! I haven't even had a chance to read other reports from Bayshore marathoners, so I can't wait to do that.