I never said it would be difficult to implement. The point was in the article Df doesnt make it clear if they are guessing if it is used or if they know. Take the recent announcement about Diablo 3. It comes out only a week earlier yet the res upgrade is implemented in a day one patch not on the disk. I question if it is used mainly because of the short amount of time since the SDK released, the fact that discs are made weeks in advance before launch and the minimum increase in res. Why bother with such a small increase. Df doesnt clarify anything about the code they are using for analysis.
We'll cover like-for-like performance on Xbox One and PlayStation 4 in a forthcoming pre-launch update, but we're going into that testing with the expectation of very close results. Differences kick in at the resolution level: PS4 hits its 60fps target at full 1080p, while Xbox One currently stands at a curious 912p native resolution - that would be something in the region of 1620x912 (assuming square pixels). The original plan for Xbox One was to ship at 900p, but the June XDK update (returning the Kinect GPU resources to developers) has allowed for a tiny resolution boost - our guess here is that 4A opted to bank the additional resource to help lock down that all-important frame-rate rather than really push the pixel-count. If so, that's the right trade.
Sounds like they know to me... the only Eurogamer assumption being, that 4A felt the resources were better met/needed for locking framerate, rather than pushing above 912p.