I cut my teeth autocrossing before I delved into DE's. Also did a car control clinic with my PCA region. Over the years, I focused more on DE's, but still did autocross.
Now, as an instructor in DE (and AX), I truly see the benefits of getting involved with autocross. I can typically tell if my DE student has any autocross experience based on how comfortable he is out on the track - how much slip angle he uses, and how he reacts when the car is sliding. And yes, the former autocrossers have much better car control skills, and understand turn-in, apex, and track-out much better than a driver who has never done AX.
A couple of years ago, I took a friend out for a session who was a solo DE driver out at The Glen. His comments on my driving compared to a mutual instructor friend was, "While the other guy is faster (the mutual friend drove a GT3 vs. my 944S2), you are more fun because you make the car slide more through the corners!" I guess use more throttle steering than the GT3 driver uses.
My point is -- autocross is a terrific tool to learn car control. If may sound boring, and you are out there a whole day for just 4-6 runs, but those runs can be pretty intense.
As for Skippy's car control school? I've never been, but it sounds to me like that would be a blast. Then again, any opportunity to throw a car around a skidpad and learn sounds like fun the me!
Just my $0.42,
-Z-man.