Subaru has to set the guidlines up for the 'lowest common denominator'.
For example, it is no secret that I autox my car, but I don't abuse it when doing so. There was a sharp turn at the last event that was an ideal 1st gear corner. I downshifted to first while taking it, using rev-match as best I could. It didn't feel good, it felt like it was really hard on the car so I didn't do it again (it did get me a better time, though).
On the other hand, I rode with a first timer at an event this year, who had no idea what they were doing. SHE would clutch in going through a turn while hitting the brake at the same time. When she wanted to accelerate, she SLIPPED the clutch. the revs were probably somewhere around 5K at 20 mph in 2ND GEAR. She would finally let the clutch all the way out and the car would take off. THis happened repeatedly and it smelled like a raccoon pooped on the dash or something.
You never know what someone has done to their car. Either through mods or driving habits/skill.
I have spoken with some Subaru emplyess about the whole warranty thing, and I believe MOST dealerships try to do the MOST they can for you MOST of the time.
Unfortunately, there is no perfect science to it.