I used to have to spend a lot of time with my now retired guy before I could get him really into the meat of the work. He was always like that; even as a young horse. Probably my technique wasn't good either.
Anyway, now I have a horse that gets to the program quickly and I can get as much quality as I feel I can expect at this point. I do it in a very short amount of time. I'm a clock watcher: I don't need a computer for help. I time everything.
It is amazing to me that I'll be trotting around and then I look at my watch and only 4-5 minutes has elapsed.
My point is...well maybe I don't even have one

Therefore, I'm wondering about all those 1 hour rides and clinics and whether they are really beneficial. I've noticed over the years the the top trainers do not spend much time at all in the work sessions. 20 minutes of energetic quality work, and that's it.
Now, if you are training an event horse or an endurance horse, then of course you need interval training, etc. If your goal is PSG or less, I don't think it requires spending a long time in a work session. I think it is far more productive to consistently schooling daily for short periods ocassionaly spending 1-2 days working a bit harder.