Tyre slashing madness!

On friday just before i was due to leave for TeAroha, Boof noticed that one of my car's tyres had been slashed. A clean hole, clearly made with a knife rather than glass or kerbage. As I put one of my many spare Piazza wheels on, I wondered if it was related to the uncomplimentary, un-signed, and hand-delivered christmas card I had received the week before. Is my stalker back? or is it merely a coincidence?