How much, is to much?

Hello all, so I have to brag and say how well Champs going lately, he's calm and really moving off my leg, his western pleasure movements are to die for, I have his flying changes down on one side and his spins are really picking up. I have rode him in an English saddle a dozen times now and he's really learning to move out, but he gets a little behind the vertical at the trot. I guess writing it down, it's not so bad but sometimes I feel like I push him to far mentally. I don't want to fry him. We do western horsemanship, reining, trail, western pleasure, English pleasure and English equitation and we ride 5 or 6 days a week. And he takes it all with stride but with some movements he gets frustrated and sticky, because my cues aren't quite clear enough. So how can you tell when your doing to much?
I suppose I am getting so used to being with people who have different horses for EVERY event, but that's not realistic for me until next year. However I am beginning English lessons on school horses so he won't have to be my guinea pig. He was taken from being a pasture pet when he was 7 to an all out show horse for the past 5 years.
Sorry for the ramble, I just can't organize my thoughts!

My suggestion would be to make sure AT LEAST 1 of those 5-6 days is spent either on a trail ride or just goofing off. Let him relax, and just wander around. Don't worry about where his head is, or if he's bending enough, etc. Let him "veg", he'll still be excercising physically, just not mentally.

My situation's similar to yours, where my main horse is my all around show horse.

Like posted above, you have to give your horse at least a day to just relax, so he doesn't start associating riding with boring hard work.
Also, during my rides, which last around an hour or less, depending on how he's working, warming up, and cooling down, is an easy time for him, so he gets that break. I probably actually only spend fifteen minutes or so doing hard core schooling on whatever I'm working on.

Don't feel strange, if your ride only last twenty minutes even. If you get on, and from the warm up, he's being awesome, don't work it past that. Short and sweet sessions, he'll learn quite a bit, if even more. Too long schooling one thing, when they've been doing it perfectly for the past hour, they just start shutting down.

If you're working something like lead changes, or spins, get three or four perfect ones, and let him be done. Pick up on it next ride, if he's right where he left off, then move on to the next thing, because he's got it.

If you don't feel like working something that day, then just don't do it. It doesn't matter to him at all. Keep it fun. If you're not in a mood to work something, then you're likely to not be as precise on it, which just isn't productive.