I have a buddy who tried this on his mustang many many many rotors later he bought a set already drilled. There is a lot to it as far as pitch and speed of the bit, cracks start very tiny but any amount of heat and cooling starts the process of warping and cracking. We talked to a guy from Steve Millen racing, he went into way too much detail but we got the point not really a home brew deal unless you have the proper set up to drill them.
