That is definitely an option and much needed in most setups.
But the point I'm trying to make is, when using trackir I try to configure the trackir curves and deadzones to allow a good amount of head movement without completely forcing my eyes the other direction.
With a small display, sitting up close, you really don't need to move your head much to look at the sides. So trackir, you would need to configure your trackir to be more sensitive, which will really exaggerate your head movements. This imho is just not comfortable, and I could understand people getting headaches and simply can't get trackir setup good enough to feel natural and comfortable. When racing, you want to look to your apex, check your mirrors and check your pass/driver windows. To do all of this on a small display, I'm pretty sure your trackir settings must be sensitive.
But with bigger and wider displays, again sitting up close, you'll need to turn your head far enough to look at the sides. Therefore, with trackir you can configure its settings to be less sensitive and have more of a natural head movement. This makes setting up trackir easier and faster, as the stock settings should already feel decent on larger displays. Then simply perfect it the way you want.
When I first tried my Trackir, I used it with AMS on my 34 inch wide display... Only settings I changed were "speed" to 0.2 and "smooth" to 2 (while waiting for my trackir to arrive in the mail, I did some research and read I should set speed and smooth that way). And I remember driving almost 10 laps straight with trackir just those minor settings. Looking to apex, checking mirrors and the side windows all just felt natural and responsive! Then I start tweaking the curves and deadzones to exactly how I want.
For a future upgrade, I still might want to continue using trackir, but on an even wider, higher resolution display.