I suggest you guys try this out before you decide it should be fully integrated in GT. It's really just a novelty. Head tracking's great for flight simulators, but it's only because pilots are constantly having to look around in a cockpit in real life, also there's no road in the sky you have to pay attention to, so one can afford to not keep their eyes directly ahead compared to driving, where it's quite important to keep your eyes on the road.
It can be useful for single-monitor applications where you can configure the TiR to "snap" over to the side mirrors once you look past a certain angle, and things like that, but I'm fine just using the buttons on my wheel for that. I like running a tighter Fov in sims, so there's times where those side mirrors do come in handy, but the rear view is usually good enough. An even better solution is triple monitors, but that's expensive of course.
I ended up selling mine off after having my fun with it. I was slower using the TiR no matter how i configured it. At one point I did get pretty close to making it effective
I know speed isn't the ultimate pursuit for a lot of people that play racing titles, it's about the fun in the end, of course. But head tracking really doesn't do much at all for driving in games in my opinion, it's just a cool, different, way to try and drive that feels more realistic at first, then ends up becoming something that just messes with your drivng, and thus fun. It really gets weird when you're going through chicanes,, or tight switchbacks where the car's pivoting and your head's stayed straight, really throwing off your rhythm. So I wouldn't recommend it.
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