The problem on the Autobahn is not the high speed, but the difference in speeds, just like in Gran Turismo 5 Prologue. People tend to underestimate the speed of others and enter the turns too fast and end up crashing into the other cars. A damagemodel will not solve this problem, it will just make the crash look better and it will make everyone suffer from the first corner on, in case mechanical demage is applied.
It wouldn't solve the problem, and in fact might make it seem worse in the beginnig as before all that happened was you got bumpbed, but now you get damaged!
But what it would likely do is push people to stop bieng the the problem. A lot of people I watch race who aren't good at it start playing GT and make all the noob mistakes (brake in the corner instead of on the straight, get behind someone and don't brake until you see them brake rather than brake where you know someone will brake) but because there is not much negative result from it (actually being behind someone and underbraking right into them can be an advantage a lot of times in GT as it screws them up and often slows you enough to get a good pass in) they never bother to get better. Being a bad driver actually works to their benefit a lot of the time so why would they get better?
However damage would make them realize they must now drive smarter or pay the price the whole race. In single player this is a great lesson to learn, in multiplayer it kind of sucks to be the guy who is teaching the lesson (as you take damage) but I think in the end it will make those who can learn to be better, actually be better, and those who can't will be forced to drop to no damage races to keep having fun.
Of course you will sometimes run into people in races who have not learned yet and the only solution is to boot them or find a circle of friends who you can drive with. But even in no damage races you occasionally run into someone who just ruins it bashing into people and going the wrong way on the track. It's just part of playing with a huge community of sometimes immature people.
So, how far should PD go with the damage? Its a game so they should not make damage 100% realistic, since even small accidents can make you loose an entire race. I would find it annoying to loose a 24h race, just because i hit a curb to hard and destroy the steering or the dampers or anything like that.
I think they should go as far as they can... I mean sure it sucks to ruin a 24 hour race by smashing a wheel in the first corner but then, don't you think thats true in real races also? The result: You learn to be more careful (rather than just hate on the damage) and you learn that sometimes you just have to pit and fix things. In a 24 hour race I assume you will pit multiple times.
For me this is the very reason I like damage (and in all truth the reason I have restarted so many races on the first lap

) it's the need to be responsible for your driving and the added pressure and excitement it adds... I can't count how many white knuckle final laps I have had where I just spent 15 minutes battling my way to the front of the pack and my car is showing the scars... I am just holding my lead, I have to nail every braking marker just right and be just cautions enough to not loose it on the corners, I have to drive the apex just right and hit top speed out of each corner AND I have to defend my line becuase the guy behind me has less damage than I do and is technically in a superior car now... I am essentially in a handicap race trying to hold the lead and I got to make the decision to do that by being aggressive... with damage factoring in it opens a whole world of exciting (and sometimes painful) opportunities to enjoy the game!
I know it might be challenging and you will allways have in mind that the race could be over in a split second, but i think it should be a bit more forgiving than real life.
The extremes of damage (ruining your car at any given second) are certainly there, but I think more important are the constant small things. The things you could overcome, but make it much more challenging like damaging your suspenstion so you can't corner as easily, or knocking your alignment out so you have to fight to keep it under control...
I suggest playing some gamse that do damage well (I always say Toca) and after a few frustrating races where you keep saying "WTF I hit one wall and no I have no chance of winning!" you will (hopefully) get better and overcoming the challenge of damage will make the races more satisfying.
Think of it moving up to damage like moving from an aracade racer to GT. The first few races are "WTF this is impossible, you can't even turn in this game and the brakes don't work!" but once you get good, there is no going back. Same happens with damage.
Basically if your skill level is maxed up without damage and you need to be able to smash into walls and others without penalty and you just can't get better... then no, damage will really suck for you. But if you can get bette (and almost anyone can with a little practice) it just makes it that much more challening, that much more real and that much more satisfying to do right.
In short, it makes it that much more like really racing... that much more a simulation
