Ha, thanks!
There was no conscious effort to try and make it fancy by differing our voices; we just had a few drinks, I set up the mic, and we went for it. It was all done rather ghetto as their rehearsal space is tiny and has horrible acoustics, plus bleed from other bands leaking into the room. That's why I used the SM57: I was able to use its rather insensitive polar pattern and high frequency response to our advantage.
My recording rig (Focusrite 2i2, Mac Mini, 19" monitor) was set up precariously atop a half stack and we used a Tech21 guitar combo as a monitor, set up directly behind the SM57 to minimize leakage into the mic.
It worked out just fine and I agree, the results are surprisingly good! I love the contrast between Kurt's smooth, talented voice and our ... er, rough and ready approach lol.
