The problem with TC is that if all 4 wheels are sliding, then 2 get grip but 2 dont, it can grab you and unsettle the car further. In most cases its good, but there are some instances where it doesnt like it. When I did the CarLimits airfield activity day you have to turn TC off for the high speed bend if TC kicks in it can unsettle the car and you wont save it. Works in more cases than not so always worth having it on, just sometimes it goes a bit wrong