Let's put one thing straight. I think Titanfall is a good game, and I don't want to downplay its achievements regarding gameplay. But. I think the most fascinating of this whole resolution debacle are these facts:
-from the very first moments of development, 60 FPS was the top priority
-it was developed for two platforms by Respawn (the X360 version being made by Bluepoint)
-they probably had whatever resource they needed... (extra number of programmers etc..)
-...and they probably always got latest SDKs ahead everyone else (given the importance of the game for MS)
So to simplify. They had a clear performance goal, everything was secondary, they had the abundance of resources (time being the only really questionable one), and yet an important project like this not only didn't manage to achieve steady 60 fps, but also looks dated and runs at a low resolution.
I think this is pretty telling.