Super unlikely. Marvel fumbled the roll-out for Avengers 2 thinking the juice of the MCU was all they needed to shut down the box office. Obviously, it did colossal numbers, but falling short of the first wasn't on anyones radar. The big problem with the 2nd's rollout is that the most successful and best movies of Phase 2 (Winter Soldier and Guardians) had issues as lead-ins for AoU. Winter Soldier came out 13 months before AoU, and then Guardians not being a part of AoU came as a major letdown. IM3 and The Dark World were huge letdowns after Avengers. They had very little to excite the fans of the universe as a whole, and were very isolated stories after the high of Avengers.
Winter Soldier fixed all of this, AND had the added benefit of the Agents of Shield story tying in at the same time. If AoU comes out Summer 2014 is probably does numbers better than Avengers.
But instead it's a whole 13 months, then everyone falling in love with Guardians and finding out that they're on the outside looking in.
This time, after four years the Guardians are in, SPIDERMAN is in, Thor finally had a fire movie that left off in a moment that leads directly into A3, and BP might wind up being the biggest solo film in the series, and plays host to what appears to be the climactic battle of this movie. They messed up the rollout for AoU but the set-up for A3 has been better than we could have imagined.