An Attack Out of the Blue

Sometimes you play games where things almost magically unfold before you, seemingly without any help from you.  "Wow, that worked like a charm, didn't it?", you marvel at your amazing attack.  Yet it did have help from you.  If you play active, developing moves and look to create threats against weak spots in your opponent's position, your pieces can develop a synergistic impact that you could not forsee at the outset.  All your pieces seem to be on the perfect squares.  In the following game, starting with move 18, Black just creates one simple threat after another, and suddenly finds himself in a won endgame, out of the blue. 

What did White do wrong?  Aside from 24. Qf2 which lost an additional pawn, it's hard to say.  Going backwards from move 26 (at which point White is officially lost), perhaps 17. h3 was a luxury White could not afford.  Maybe 17. Rae1 would have prevented everything that happened.  But it is really asking a lot for someone rated below 2400 to see all of that.
I think the lesson here is not what White did wrong, but what Black did right.  By placing his pieces on active squares and creating simple threats,  White pieces were forced to move in such a way that squares previously unavailable to Black became accessible, which allowed the creation of new, unforseen threats, which eventually became indefensible.  You see the same thing in tennis: a player hits the ball to the right corner, then the left corner, then the right, and repeats that simple pattern until he gets a weak return or a lob that he can put away for a winner.  No incredible, miraculous shots.  Just good, solid shots into the corners can create a winning situation.  Sometimes just sticking to the basics can yield great results "out of the blue".