The conditions were pretty rotten for my birthday: high humidity, temps 18-20 degrees too high; wet, slippery rocks. But I ran my visualization as if I were a character in a book. It was the strangest thing; I was so much in the zone that I almost didn't exist.
And I ran a sub-55 minutes, comparable to what I used to do in my thirties: 54:53 at age 58.
My recovery drink was Frog's Leap cabernet. Now taking a week or so to plan the book and my next moves. Meanwhile, thanks for all the kind words and happy thoughts.