I had a situation the other day where TACC nearly had me run up the back of a car - it appears there's a blind spot for TACC.
I'd come from the M4 east bound and was transferring to the M7 south bound. I'd left TACC on while I was on the slip road. It had slowed to 90 then 80 and had then increased to 90 then 105. As I was about to enter the M7 there was a slow car passing the exit in the left lane. TACC missed it completely and I was only a couple of metres from hitting it when I braked to turn off the TACC.