Accurate no, but (like we've discussed in the past) I like to set it up so it's at least "animated" in a satisfying way... i.e. a little bit of fade creeps in if you go through a tough section that taxes the brakes or on a long stop from vmax. Might be worth reworking a bit for that, if nothing else. But yes, I absolutely consider brake heat in vanilla a "game mechanic" more than a simulation parameter.