If the air lines were to be cut, as shown, the brakes would actually lock up, not cease to function... See more
You might say that Bonnie is K.I.T.T.'s mother. She takes care of him with all the maternal love and the ferocity of a tigress.
Michael's kidding. Eh, K.I.T.T. is his, I just put him back together again.
And Michael gives her a great many opportunities to do so.