There are a lot of options and variations, and much of our stuff can be configured in more than one way. It would make sense that using a single floor wedge would reduce polar anomalies and therefore maximize gain before feedback. And we attempted that with reasonable success with the L wedge. At Coachella, Jane's Addiction had a single L wedge on both Dave Navarro and Martyn. I think it comes down to coverage and perception.
Perception is the main dilemna.
I put a lot of time into the Microwedge design, and realizing that wedge pairs are not going away soon, I really focused on getting them to be able to function in pairs. There is an advantage to that stereo sound of two properly spaced wedges, combined with the increased coverage realized by the pair. If the artist pics up the mic, all bets are off and the rear lobes of the various mics are all gonna catch the wedge sooner or later, so dead center would be the answer. I am going back to a follow-up amplifier question. We are contemplating building a Powerlight or Chevin 2 mix version as the Microwedge 12's are designed to be small and light enough to fly as excess baggage on commercial flights in an ultra-light case.