Guide

New safety car and race flags - Update 3.600

Actually doing that last lap like that is not doing it right. You seem to have not noticed it but the game actually does somewhat respect physics here (It's not that accurate in doing it as it has to rely on quite simplified rules to be able to calculate such many cars in such many races at the same time). Boost is actually applied on accelerating, so you can make up slightly more time on worn tyres through boost as you have to do more accelerating from having to go slower through the corners but you're still better off doing that boost lap on tyres not worn as you loose less time in the corners by being able to go faster through them.

It's a first step. There had been suggestions to both somewhat spread those failing bot cars and also prevent the same cars failing every race and also introduce possible active cars retiring by giving Cooling and Reliability real weight and thus have managers balance performance and reliability. While this still would be something random and has the chance to ruin ones race by taking out either your strongest opponent or yourself it'll be at least somewhat based on choice and who knows, maybe the system we get even works out and allows a good manager to be fast enough in races for results allowing him to become champion while, and probably sometimes because, still managing to always produce reliable cars.

I'm afraid it clarifies not much as the link between how shaving off quite a bit of lap time due to greatly improved acceleration on straights makes cars spin off in a corner just makes no sense to me. Worn tyres or not. The only thing making sense here would be asking if the delta between maximum grip and the one needed to transmit the torque from the engine would allow such an increase in acceleration without making the tyres spin helplessly but that is entirely possible within the scope of physics.

Same with the train and dirty air. There's no link but for the fact that with too much dirty air there's no train as the second car can't keep up well enough to stay within a second. The first car in a train has no dirty air and why should it, it's running in clean air, so why should it go slower than cars of similar performance not leading a train? The ones behind are in dirty air and this is clearly visible as the gap between the first car and second car increases as it can't run the same lap time anymore, while the third and following are still stuck at a gap because they can't get closer and overtake as coming closer to the car ahead increases their own dirty air above the one the car ahead suffers from. This behaviour is also not against physics. 
Now the train enters DRS and given they managed to stay within a second all but the leading car are allowed to reduce their drag drastically which results in greater acceleration allowing them to cover that distance in, give or take, one good second less on average than the leading car and thus allowing the second and sometimes third car to overtake it. The second car can overtake the leading car because its total lap time is faster than the one of the leading car in clean air as it gained more from DRS than lost from dirty air. Thus cars alternating logically have a lower average lap time than a single car that isn't loosing (less) time through dirty air but also isn't gaining (more) time with DRS every second, or even better, two out of three laps. That's also fully in the scope of physics.

The 2 biggest questions here that I see are: First, could dirty air be really such different between the tracks. Well, no-one said that the cars of an iGP formula don't have to use, or are allowed to use, different aerodynamic properties on certain tracks. So yes, even greater differences are possible without bypassing physics in any way. 
The second would be the advantage the DRS gives, but that's also perfectly realistic and in scope of physics if, for example, the iGP formula requires the use of air brake elements for just this purpose, something Formula One also did in a milder, less effective form in the specifications for wing elements, or the DRS also allows things like opening a bypass of the engine air restrictor for a some extra power.

Bonus question: Couldn't the game take tyre wear into account for how much boost the car can use as the grip needed, while not impossible, seems a bit high, especially from accelerating out of slow corners and using low wings? It could and I think I would like it if it would.

One word: Brakes

I know what it looks like, but even though less drag is the reason for the advantage for both the train and that cycling peloton the workings are pretty opposite, though. The cycling peloton gains its advantage through power conserving in slipstream in a larger group with leading and lone cyclists having the hardest time. A small group of cars (in a train its usually the first 2-4 cars giving it its speed, the rest just sticks to them by getting DRS every lap) gains from its cars getting DRS more often than lone ones but fight dirty air most of the time, with the leading and lone cars having the easiest time and being the fastest there. It's just that DRS on one straight usually outweights all the rest of the track. In F1 that isn't the case, which so often makes its races so boring as it does have the dirty air.

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