I also don't know about the "teach you more" part. I think it's more correct to say that less powerful cars keep you out of trouble more. On a more powerful car, you have to learn more about the throttle control, versus on a 2.0 NA engine where you can just mash it and go without worrying about spinning out(okay, don't try that in an S2000).
In the Caterham you could spin the car by shifting down too aggressively. The car had more torque than grip, like a litre bike.
I have to disagree though. Less powerful cars/bikes teach you so much more about momentum and proper cornering/braking. 'Throttle control' is the easiest part.
I see a lot of people saying the same thing but I still don't quite see it. There are a few more legitimate reasons I can think of, but even they have their counterpoints:
- Old, less powerful cars are cheaper, so if you put into a wall, it still sucks, but you learn to move on. Less so on a powerful car that costs more, so you might be willing to push the cheaper car a bit harder. On the flip side, though, depending on where your car crashed, an older car has a greater chance to leave you more seriously injured(unless it's fully roll caged or something of the like). I know tracks usually have things to soften the blow, but there are still times where space constraints kick in and you crash into something hard.
- You will push yourself harder in a less powerful car trying to keep up with better cars, but then unless you have something like a GT3 RS, then there is always a faster car on the track for you to push yourself. On the open lapping days, my best lapping times are actually from me trying to keep up with a C7 GS and C8 Z51 on two seperate days. Corvettes are always fun to play with for me.
- Some say a faster car have more power to cover up mistakes, but a mistake is mistake. You still add time to your lap time. Any person who is seriously trying to learn won't compare their own time with someone else with a very different car. You compare to similar cars and that's mostly yourself. For example, I won't try to compare lap times to a Miata except to know if I am doing something
very wrong with my Camaro, but the times from, say, an M2C would be something to look at. Especially if you have telemetry, you could review the footage to see exactly where and what you did wrong.
And then there is the elephant in the room: the linework is completely different for a lighter and heavier car. They require different emphasis and strategies. Whereas carrying momentum is the trick with lighter cars, where and how to use the throttle becomes that much more important on a more powerful car. Yes it's easy on paper, but again with telemetrics, you'd be surprised how much you can learn. "Proper cornering" is simply different depending on the car you drive so proper cornering in a Miata isn't directly translatable to proper cornering in a Z06. Braking is just as important regardless of cars, again, mistakes are mistakes. They will impact your time.
Really, I think you learn the best when all the cars are relatively equal on the track, so the strategies and skills required are the same for every car, and it boils down to your skills.
We can argue all day about what you learn more on and it seems like some people would agree with you, but you also have to realize that different people learn in different ways. For some people, learning in a Miata and doing all the momentum carrying is fun, but for some, being passed by a bunch of other cars in straight lines can be discouraging. What good is learning more if you eventually lose interest? That's where a more powerful car could help. It could be a good way for unskilled people to have some dumb fun on the track more forgiveingly, stroke their ego and hopefully even get them interested in tracking (like me). Open tracking days are not even that serious to begin with, anyway.