You can if you want. I never have, I'll loosen the cinch and lift up the saddle a bit, to let some air under it, but I don't completely unsaddle. Partly why I don't is if you can get out of the P&R fairly quick you can pick up some extra minutes. They take the readings at 10 minutes, but you get 15 for the stop. So if you get out quick you can pick up 4-5 minutes. Doesn't seem like much, I know, but with 2 P&Rs that's 10 minutes, and that's 10 minutes you can use to let the horse move slowly down the trail, which IMO, helps more then taking the time to have to resaddle. Moving slowly will cool them down faster IMO. I think this is called "strategy":)
Becky
Sounds like a reasoned 'strategery'