I can say with certainty that training like this would have been hugely beneficial to me when I first had my permit / provisional license. I can recall a particular instance when it had rained and I was still driving a 1968 Chevy Camaro 350 4spd (tiny old tires and lots of power not a great combo in the rain to begin with). Keep in mind this was before I had ever even driven a true racing kart or been instructed at all in car control let alone been told what to do when a car began to slide. It was also my first ever experience driving in the rain (I live in So California after all). So I started my way around this corner and the back began to go and I had no idea what to do so around I went and I was absolutely certain I was going into the store they had just built on the corner.
Luckily the curb stopped me before that happened. But knowing what I know now I am certain I would have been able to 'save it' and would have a much less exciting story to tell now, and maybe the rain would not completely shut my brain down on the race track...
Long story short I would recommend this to anyone and I do on a regular basis. Still trying to convince my girlfriend to do it so maybe I could relax a bit when I give her the keys. It should be a mandatory requirement before being given your license.