What does Steve Slater mean when he screams (which he often does), “Look at thaaaat. Kimi is ab…solutely on the limit!”? He means to say that
(1) Kimi is wringing the hell out of his Ferrari.
(2) He is pushing his Ferrari to its limit and (very frequently) beyond.
(3) He is driving (thrashing would be more apt) his Ferrari with a ridiculously low factor of safety that one small slip-up (read that as a braking point missed by a few metres), he along with his car will be promptly in the wall!
(4) In short, Kimi is driving at “Ten-Tenths”!