Stereo micing phase issues

This can work when recording a single source, like two close mics on a guitar amp, but when ambient recording a collection of instruments like a drum kit there can be problems.

This is because you have to pick one of the drums to judge the phase by, say the snare.
When you align with the snare you change the phase of the other drums and cymbals that are different distances from each mic. So by aligning for one drum you tend to compromise the others.

Also, any ambient reverb is also phase shifted, which can do odd things (more comb filtering etc). This is why delaying or advancing a track is not the same as changing the mic position in the room.

Still, if it sounds good, do it. There is no such thing as true stereo without some phase differences (otherwise it’s panned mono). I think that moving the mics leads to less weirdness in general though.