> Unfortunately, the early moves in the game ("Joseki") are the most important. They are also the most difficult to learn.... for rapid improvement, the only real way forward is to play lots and lots of games to learn how the early game flows. Direction of play, which side of the board is most important and other such details.

> To put it in perhaps more concrete terms: playing a "tactic" position may net you +10 points across a sequence of 5 moves or so. (IE: One well placed tactical move, and ~4 followup moves may capture 5 enemy stones + 5 territory simultaneously from your opponent). However, every single early-game move is worth nearly +20 points of territory if played correctly. I'm serious.

Sorry, but this is complete nonsense. "Play lots and lots of games" is the only part I can get behind. I have seen tons of people get well past the beginner stages entirely self-taught and with a focus on fighting because that's the easiest thing to self-teach. A few basic joseki sequences go quite far (especially now that AI analysis has done such promotional work for early 3-3 invasions) and people who try to figure out the rest by intuition generally make smaller mistakes than those who can't read out squeeze sequences or don't understand semeai theory. Of course joseki are important to know, but emphasis on them often leads to a false confidence in having mastered the opening for students who aren't thinking about direction of play or other fuseki issues.

If a tactical sequence appears to net you 10 points against an opponent who is playing correctly, you basically already had those points. (Well, half of the points for most capturing sequences, since they'll usually end in gote; but then you have to consider the opportunity cost of tenuki.) This is as true for capturing sequences as it is for invasions and reductions. Which is why students are counseled to be very conservative in counting frameworks; they are not territory.

If a tactical sequence actually does net 10 points because of your opponent's misplay, that doesn't mean that your moves were only worth 10 points, or even that each move was only worth 10 points. It means that your moves were worth 10 points more than the opponent's were. Similarly, correct early-game moves may be worth a lot of points (compared to passing, the reference value), but most incorrect moves are worth almost as much. Even things that are marked as clear mistakes in a joseki textbook, with clear refutations, might only cost one or two points (although, yes, they can be catastrophic; and of course pros do have to worry about every point). So this is very much an apples and oranges comparison to the "value of moves in the opening".

But also, that value is about 13, definitely not "nearly 20". We know this because even now that we have ferociously strong AI players (who inherently make moves with a higher average value), they still accept a komi of 6.5. And if you ask them to evaluate the first few moves and let some of them be passes and see the change in the score, you'll rarely see 20-point swings in any opening, but you can trivially create such positions (and much larger swings) in middle-game fighting.

> That's why when you watch top-level Go play, there's a lot of "teleporting" across the 19x19 board, searching for the most important positions. And there is also very, very loose play and possible sacrifices / aji. (Maybe its not a true sacrifice, but you'd be willing to sacrifice if the opponent over-extends).

Sure, but 10 kyus can do a reasonable facsimile of this as well. They just have bad timing, or make bad choices about sacrifices, or have wrong ideas about how to use the aji.