They announced the Engine change last Autumn, and then it turned out the Engine change was actually prior to E3 2013. Do you see where i'm going with this? Combined with the fact they said what they just showed at E3 was just a snippet of the full assets, and I'm led to believe the basic foundations were completed at least a year ago. My further reasoning is that they do this because of what happened last Gen, and so, they withhold on the true progress, and we then see it sooner than we're led to believe.
I will admit I could be wrong in this instance, but recent revealments feel like this viewpoint has weight. Whether it looks worse to you not is up to personal interpretation. I'm just trying to view it neutrally.