LOL cause I guess I'm just that fast... :P Don't worry, other people will answer your questions too. They're just getting up yet.
I think the most stressful part is getting everything ready. Rushing around with last minute bathing, tack checks, getting everyone loaded and going.
Once you're there, it's a lot like a typical lesson warm up. You get your horse all groomed up, warm them up in the ring (except there are a LOT more riders in there than at home!!) and then you enter a class and hope for the best.
But the prep-show work is very stressful, especially when you're running around trying to find your horse's sheet or you got soaking wet giving your horse a bath or however it goes.
But it depends on the show. The higher you go up, the more intense it gets. But local shows are quite laid back for the most part.
"Strength is the ability to use a muscle without tension"