Thanks for all the feedback on my original post -
several of the thoughts mentioned had gone through my head, some of them were
new ideas that I hadn't considered.
The takeaways I have from the discussion
are:
1. continued vigilance & keep going slow (stay
the course)
2. look carefully at my electrolyte and
cooling protocol and improve upon it - having a fit horse from the start has not
made me work hard at optimizing this stuff... It's time.
3. if there's a next time, let her roll in
the sand and see if that's all there is to it (Maggie's post got me thinking
that it's quite possible my mare thought she was done at lunch, since she isn't
used to the 3 day format and she *always* gets a roll in the sand pile at
home at the end of a ride).
I will probably punt on a 50 in late Oct., and wait
for Spring when clipping my fuzzy beast is a better management
option.
I would like to comment that the hardest part of
being where I am with my horse is knowing what my horse "usually"
does. Three days was a new thing for her, and I know she wasn't excited
about going out the third day... Our rides aren't usually two days in the
mountains where it's cool, and a third day in the desert canyons where it's hot
(very hot for a horse building a winter coat). I expected heat to be the
biggest difficulty on Sunday, and planned to go slow, but was still suprised at
the impact. Since she's an ex-racer, almost every competitive ride offers
some new behavior for us - at this ride, she walked out of camp on a loose
rein each day. :-) That is kind of odd, too. We'll
just keep trying to make progress slowly...