Given the strong slipstream effect of the game, if cars are unable to overtake, the field will become extremely compressed. This we drastically increase the risk for collisions in the corner following the straight.
Let's play a little thought experiment. We have drivers Alan, Bill, and Chris entering the straight, in that order.
Scenario A - the drivers play nice and make room for each other.
Alan is in front, so gets no draft. Bill and Chris will both pass Alan, and it's a pretty long straight so Chris will probably pass Bill too if he doesn't make a mess of it. Alan picks up their draft as they go past, and stops them from pulling away too much.
The order at the end of the straight is Chris and Bill, with possibly a small gap to Alan.
Scenario B - the drivers drive defensively.
The drivers all choose not to make a move, based on the inherent danger.
The order at the end of the straight is Alan, Bill, then Chris, the same as when they entered the straight.
The field is neither more nor less compressed, it's simply in a different order.
The problems with enforcing Scenario A that I see are twofold.
Firstly, it removes a tactical decision. It's true that often drivers will want to cooperate with those around them. But that should be a choice that they make based on their situation, not something enforced by the rules.
Secondly, it creates the odd situation that in the final lap, you do not want to be first coming into that straight. If the rules prevent defending, you absolutely want to be behind your rival coming into that stretch. Due to the way the draft system works, if there's substantial straights on the track that's always going to be true to some extent. Making defense possible on that straight simply means that you want to be second coming into the final section of the Mulsanne. However, the further away from the finish line we can push that straight, the more time there is for racing skill to kick in and decide the winner instead of the stupid draft. It gives another corner or two of racing to that final run to the line.
This series is idea is to similate reality as much as possible. Cars at Le Mans do not block each other on the long straights by leaving no space to overtake.
I'll repeat what I said to Paginas. Back this up.
As I mentioned before, due to the nature of Le Mans a lot of the passing is going to be either under blue flags or between cars which are not in the same class. Those passes are expected to be uncontested. But stating that two cars competing against each other would not drive defensively is odd to me, particularly if this is a Le Mans specific thing.
I know that there are limits and rules to how you may defend your position in real life. This maybe be one of them. I can't see anything related to on-track behaviour in the Le Mans regulations here (
http://www.lemans.org/en/race/24h/regulation.html), so for now I'm assuming they're using standard FIA regs (
http://argent.fia.com/web/fia-publi...75FA00440479/$FILE/Annexe L_2009_09.07.20.pdf) as that's the license you need to drive there. FIA regs are basically the same as what we have; no sudden moves that could cause damage or injury to other drivers.
If you can demonstrate some evidence of your statement, that'd be great.
Edit: Watching footage of Le Mans. The real track is SO MUCH wider than the game. You could fit at least three LMPs side by side in real life. THAT's why you're seeing people get "let" past in real life, because the truth is that it's indefensible.