The trick is that if it's not working, don't just fail backwards to Cena. Look to who IS getting a reaction, and nudge things that direction. The problem is that every time they've panicked about something not working, the next move has been to go back to Cena, and at this point the crowd is conditioned to that. Run with Reigns as the guy. If Reigns isn't working out, you start trying to work other guys into it. Most of the other times they've attempted to elevate a guy, it's been with the secondary title, so the crowd is always going to see them as secondary.