That would be completely hopeless in a crowded high speed racing situation - e.g. T1 mayhem - and unfortunately a crowded high speed situation is exactly the place where the look buttons are most important. You need to be able to see to either side for only an instant and then be looking forward again or you will cause accidents !
I'm not sure about 'look at nearest car' - I would have to experience it before judging, but it is certainly missing on of the features that I find 90º look so useful for.
With 90º, you can easily see if the guy/gal beside you has fair overlap or not (and whether you do). With the look at car feature, I would never use it unless it was instant, and in that case, it would be difficult to judge how big an overlap the car has.
Another problem is that it is likely to be disorienting having your view changed in an arbitrary way that depends on the position of another car that you may not even be aware of - I'm pretty sure I would prefer to have a dependable 'look' that always did the same thing. That way it can become an instinctive part of my sensory input rather than a puzzle for my conscious brain
I've said elsewhere that I believe that 90º instant look is a good and fair compromise between fantasy and reality as a way to counteract the lack of peripheral vision when using a standard PC monitor.
When I race, I (used to) tap the look button, I see to the side for maybe 2 or 3 frames, and I'm looking forward again before my brain has even finished 'realizing' if there's another car beside me or not - it's a really intuitive way of getting better spacial awareness.
IMO the guys claiming that you don't ever turn you head 90º in a race car are missing the point! In real life, even with a helmet on and a harness, you should be able to get 180º of visual awareness with minimal head movements maybe 20-30º each way. The 45º look just doesn't do it, and now the 90º look is just way more awkward than it needs to be.
I know it is 'un-realistic', but this is about counteracting one very un-realistic problem (lack of peripheral vision) with an equally unrealistic solution (90º instant look) in order to make the overall experience more realistic.
ok, enough... soapbox anyone ?
Col