Sort of software and hardware, but I think more software. I'm going to assume that TACC uses regen braking whenever possible. In slow traffic and close distance, I imagine it's a lot of friction braking. Sometimes I can definitely feel the friction braking if the car in front goes from slow to zero quickly. My question...is there any indicator that shows when friction braking is used? Not just black or green line, I understand that. I'd like to get some sense of whether my manual driving is more efficient than tacc in these situations. On a tangent, is it safe to use tacc to go down a long, steep grade? Willl you know if the pads are overheating? I don't like to suddenly find out that I have no brakes. Tangent to the tangent, I've read about folks knowing their brake temperature, where is that info? Thanks!