Corrected entry: The wheel of Bond's car is cutting no more than 4-5 cm into the ice. Nevertheless the ice cut is 15-20 cm deep. And it's not just broken off by the weight of the police car. It is a totally clean cut, so the ice was cut with a tool which reached deep into the ice.
JC Fernandez
6th Feb 2008
Correction: Your conclusion is based on your knowledge of how the filmmakers produced the cut in the ice. The reality is that lake ice is treacherous and is strongest near the surface. Bond makes a cut on the surface of the ice, so the ice is weakened along this cut line. Add the weight of a car on top, and absolutely the ice might give, and cleanly at that.
JC Fernandez