Thats kinda how i pick placement for subwoofers. Ill put the sub in the listening position then walk around the room to hear where sounds the best , mark that spot then start positioning the speaker in that location. I say start because setting up a room properly takes time.
Move it around until it sounds good! Ultimately it can come down to trial and error, but the further the mics are apart, typically the less phase issues come into play.
