Thanks for the kind words. I may be able to swim a long course 800 in June but I will have to make sure that I don't first swim a 1500, although I did manage that in 2008 when I recorded best times for both events.
My best times are very slow, of course, and I am a long way behind the chap who won in my age group the other day, who finished in just over 29 minutes, which means that he was stringing together consecutive fifties at just below a minute. My best time for 50m is 57.41, so that doesn't seem like a viable proposition without something akin to a miracle.
Perhaps lots of sprinting practice?