Independence is unsustainable because the money gap between independence and P5 would put us at too large of a disadvantage to compete. If we were to return to the MWC, the money gap would grow even wider. It just doesn't make any sense to return to the little-kids table.
Circumstances could change down the road and we might be forced to join a conference but the way things are right now, we are going to be independent until/if a P5 invitation comes.