@hotak The views of those involved in the development of sims, such as those used in research and development, are very interesting. You mentioned that tire models fall into three categories. If you know the strengths and weaknesses of "Tame Tire" and "Fiala Tire", can you tell us? This is because rFactor2 may be used in Tame Tire (partial?) And Fiala Tire may be used in AC / ACC / iR.
AC/ACC tire model is not considered to have much in common with iR. rF2 is closer to iR in that both use a physical tire model where you begin by modeling an entire tire, which in rF2 case you then run through a bunch of tests to generate the look-up table.
Kunos only recently moved away from a one-point into a five-point tire model (you can read more about it here). The model that ACC, or at least AC uses is not that complicated, it's more related to the magic formula type, which is why it's relatively easy to build mods for. Then again, a more "complex" model isn't automatically better or more practical.