If this was the GGG we saw vs Geale/Proksa/Macklin, I think he beats Canelo in an 8-4 or 9-3 decision that probably ends up an MD for GGG. Golovkin has clearly gotten worse over time whereas Canelo has clearly gotten better. At his peak, GGG was a more defensively responsible boxer, had better stamina, was a bit faster, had more pop to his shot, used a more diverse arsenal of punches, and wasn't trying to force his "Mexican style" bullshit (IMO he got worse under Sanchez). That's not to say that Canelo wouldn't have his moments, but even the best Canelo we've seen yet was still taking a past his best GGG to a highly competitive MD. It's hard to see Canelo beating a peak GGG.
It's entirely possible we haven't seen Canelo at his best yet, so I might change my mind depending on what we see vs other MWs, but even the Canelo we saw the other night still isn't good enough for 2013-2014 GGG IMO.