Definitely no need to overthink it. Position the mics until everything blends right and SOUNDS right to you. Experiment with polarity reverse on the way down. Whatever sounds the most in, roll with it. If you have problems down the track, only then experiment with nudging everything.
There is a camp out there who make sure all their mics are as in phase as possible by nudging afterwards and honestly I've only ever found that to sound weird to me. The transients become stronger and fatter but the ambience of the kit diminishes somewhat. Anyway, in a sample-replace heavy genre like metal it isn't so crucial.
As far as the 3-1 rule goes, I've always thought it, and been taught it, to mean that the mics should be at least 3 times the distance from each other as they are from the sources they mic. Now I'm not particularly sure how this can apply to spaced pair overheads where both are essentially mic'ing the same source. The bleed from one is essential to the other because that's how the drums are positioned across the stereo field. It's not gonna be the strongest image in the world given the inherent imperfections of the technique, but as long as the phasing between the two SOUNDS right (particularly in mono), who cares? Joe listener isn't going to sit there and measure how many degrees out of phase the 3rd china is during the breakdown.