How to Win in Positional Chess: Squares

Supposedly, chess is 99% tactics. Is the remaining 1% positional chess?

Well, this highly opinionated discussion is not the point of my post here, though I do believe almost all aspects of chess are tied to tactics. This will be a multi-part series on positional chess aspects which if you master (which I have not!), your chess skills will soar. Today's topic is about squares. Here is a blitz game I played recently:

In the diagram above, Black has a much better position due to his Bishop pair and space. White's last move was Qg4, and Black commits to 12. g6?!. g6 itself is not a terrible choice (and my position is still better after I played it), but as we see, the Bishop intends to go to g7 (and if he does not, the squares around the Kingside will be weak!), and when he does, the d6 square is no longer defended. This may not be a big deal now, but it is blitz and anything can happen... here is how the game finished:

So as we saw, g6 was not a blunder in itself, but White was able to formulate a winning plan and pounce on my mistakes due to one little square on d6! Though this was a blitz game (and the loss was painful!), I thought this was an instructional concept. Feel free to comment!