I'm still trying to work out if that was a tongue in the cheek posting or not, Rory!
This sweating up between the hind legs stuff is something and nothing. When it gets hot, horses sweat. Humans sweat. Everyone sweats. This does not in itself indicate that the horse is going to run badly; some horses have even been known to win having sweated up behind the hind legs! The thing is that it is often used as an indicator too rarely to be of any use; can you tell me that you have inspected Youmzain between the legs on every run on a hot day, for example?!
I think it was Johnny Francome who decided to expand on this gem of a theory on Channel 4 one day and ever since people have latched onto it. In itself it means little I'm afraid. Horses still sweat and win, especially on hot days. Horses still sweat and don't run below par. Horses still don't sweat and do run below par. It goes on.
Oh, and what were you saying about excuses EC1??! Of course, as he didn't win, Youmzain must have been below par, no other reason for it....
(and no, Youmzain does not possess a turn of foot)