Recently verizon let us add tethering plans to certain EVDO phones. They specifically said we can use USB cables for tethering but not Bluetooth.

I know for a fact you can tether an E815 via bluetooth (or at least some of them) via bluetooth because I have done it. My ipaq flew through data very quickly. Does anyone know if there is any way for them to actually tell if you are connecting via cable or bluetooth? If we have tethering plans, can they do anything about it?

Thanks
crazyjeremy