I actually think the 12-14 period of Djokovic's might arguably be the most disappointing of his career considering that, the way I see it anyways, he didn't gear his evolution as a player towards the right direction. From what I gather (I didn't follow tennis too closely, just sporadically during the 12-14 years and I'm going mostly off footage I've seen after the fact), during the 12-14 years it seems Djokovic opted to trade in assertiveness, aggression, power, and killer bite in his game, and instead opted too deep towards a counter punching, neutral, "pusher" profile of a player, but he often seems toothless to my eyes during those years as a result, and I consider that a disappointment because to me at least, his potential as a player is much much higher than what he and his team opted towards during that time.
My favorite footage of Djokovic might actually be some of the stuff seen during chunks of his 2008 and 2009 years. To me, the 2011 season is likely his greatest because it's arguably the season where he best balanced that 2008-2009 aggression with that cerebral consistency, determination, endurance, and clutch-ness he's become so legendary for.
Just off of those clips you can see Djokovic could actually be as aggressive and heavy hitting as a Thiem or Alcaraz if he wanted to, his forehand motion looked beautifully ferocious, and this was despite him being as thin as a noodle and probably not having his racquet geared out to prioritize power in the first place. Even in his 2011 season he wasn't that explosive.
Even then though he still had problems hitting heavy enough of a ball if he didn't have the right amount of time, angle, and if the ball was low. Low balls have always seemed awkward for Djokovic, especially off the forehand wing. I would have thought someone as talented as he is would have met that challenge better throughout his career.
To me
THE blue print was to get that 2008 Djokovic that could seem like the perfect player off of both wings at times and magnify him, iron out his forehand deficiencies,
literally become the perfectly balanced attacking baseliner who could also defend like no one else could all at the same time. More or less what he became in 2011.
Djokovic went on to iron out most of the deficiencies he had as a younger player but in the process generally lost that younger, more aggressive version of himself altogether in the years immediately after 2011 imo.
Then in 15-16 it's clear he hit more of the bullseye of what he was aiming for during 12-14, but there was always still something missing there with the weight of the ball generally imo.
The best of Djokovic, when he really has looked like the GOAT pound for pound, has always been when he's played more akin to the type of player I described in light purple up there.
Whether it be against Nadal AO 12, Ferrer AO 13, Nadal MC 13, Nadal Doha 16, Federer AO 16, Nadal AO 19, etc, post 2011 he's been at his best when he's combined the more surgical version of himself with a stronger weight to his ball.
But even then, there's something to that Djokovic of 2007/2008-2011 that has only sometimes risen up to the surface during the years, and they make me ask what could have been if he had decided to be generally more stronger, attacking and aggressive throughout his career.
Which is why the AO 23 version of Djokovic might be my favorite actually.
There are times I watch Djokovic footage during 12-14, and his whole career really, where it looks like he couldn't generate more power even if he wanted to. I don't get it. Where does that lacking come from? With a little more of that disposition from his earlier years I don't think he loses against Wawrinka all those times in the slams, for example,
and I think he wins 1 or 2 more of his FO finals against Nadal.
