Another question?

You know the answer to that.

Opening theory is useful to almost all correspondence players. I focused on the use of novelties, but that doesn't preclude players just following along.  I generally follow theory as long as it's beneficial to me. Others follow theory without realizing they are going the wrong way. Perhaps I'm optimistic in thinking such correspondence players will eventually learn from their mistakes. I did play one cc game against a NM which followed theory for about 30 moves then we agreed to a draw. I was Black and was very happy with the draw. 

Most games will leave theory at some point. The new move could be a TN (theoretical novelty) or TL (theoretical lemon).

Kindaspongey, 

Willy Hendriks' book, Move First, Think Later: Sense and Nonsense in Improving Your Chess, is really interesting. He makes many controversial claims in that book, but his opinion on studying openings, as you presented it, is actually more or less the orthodox position among chess coaches.

However, Willy Hendriks would almost certainly not approve of the general handwaving and wordy responses that occur in these threads. He believes that words often get in the way of chess understanding. His basic thesis is to analyse moves, and not worry too much about whether a good move fits some dogma. 

This goes just as much for the opening as any other phase of the game. If a concrete move order refutes a general principle, then the general principle was the wrong one for that position. Studying specific openings will help to recognize the importance of tactics. 

Here's a rather banal example of a concrete move refuting a general principle:

Who, at the moment, is making claims about what Hendriks would or would not approve in these threads?

"In these threads", is it being argued that tactics do not have importance?

Does this justify a belief that the typical plans of the opening are not relevant to players under 2000?

"... I feel that the main reasons to buy an opening book are to give a good overview of the opening, and to explain general plans and ideas. ..." - GM John Nunn (2006)

Let's take a look at a "boring" opening played by Petrosian:

It's interesting to note that after a rather obvious looking move in 7...Qb6 White was basically forced into tactics immediately. He played actively throughout the game due to one little poke by Black. Of course he could've played 8.Qc1 and avoided the tactics but he'd be forced into playing passively even though he did nothing wrong. I'm rather doubtful that all the opening plans in the world were going to help either player.

Now imagine what happens between two club players that play into the position after 7...Qb6 8.a3. Do you seem them playing all of this because they read a book about the Slav defense?

I have no clue who you are arguing against. But whenever you're proven wrong, you resort to the claim that you never made a positive statement, it was just a question.

Whats Opening Therory?

In this thread, is there a specific statement by me that you imagine to have been "proven wrong"? Do you think it is appropriate to claim that a belief of mine has been "proven wrong", if I never stated the belief?

Is it realistic for a below-2000 player to try to be like Petrosian and/or Sorokin?

About 11 days ago, penandpaper0089 referred to "those +/= positions the opening books like to rave about." I think that gives some indication of what was initially being discussed.

This gives an indication of the focus of my contributions in the last 7 hours.

How do you know ...Qxb2 is bad? Does it just look bad or is there proof? Did that proof come from intuition or was calculation actually necessary to prove that it's bad? What about ...Qxb2 in the Najdorf or the Trompowsky? Can you eye-ball those positions as well and come to a conclusion? Often times terrible looking moves work just fine. There were plenty of ugly moves that Black could have played in the game and interestingly they all required great calculation to prove they were not sufficient. Whether ...Qxb2 was justified or not, White needed to be able to calculate lots of potential lines in order to prove it. That's the point really. Knowing wasn't even half the battle in this case.

The fact that Black may not have played as well as he could is even more telling. Despite the fact that Black made these errors White had to play with amazing activity to be able to prove that these errors were actually relevant. This is another point. Anyone can look at the game and say, "this shouldn't be here" and that shouldn't be there." But could anyone prove the point with the activity and calculation ability shown in this game? If not White would be a pawn down for nothing despite having a more aesthetically pleasing position.

And finally, how relevant are Slav defense themes here if the position is not even a Slav anymore? Instead we ended up in some kind of isolated pawn game with an extra pawn for Black. It may not even be important but f4-f5 is actually a known plan in isolated pawn games when there is no bishop on c8. But that's a typical middle game plan and not simply some opening theme. Opening books will rarely go out of their way to deal with things like this because that's typically not what they're made for.

But Petrosian's ideas on the play are the most illuminating. Sorokin may have been fully aware that this is a dangerous way to play and he may have done it simply to change the nature of the position or to try and defeat his opponent in the complications. Were I playing White here against Sorokin I doubt I would find Petrosian's resourceful moves.

Perhaps at higher levels it's not a matter of understanding, but a novice's lack of precision due to not understanding the position is the same as... simply not understanding the logic of the position

No not at all. It is realistic however that you could be forced into complicated positions that don't resemble your opening of choice or have any themes that you can latch on to at all. Your book knowledge may not be very helpful there. It doesn't help much that this happens in just about every game of chess.

penandpaper0089 wrote (~6 minutes ago): "... It is realistic ... that you could be forced into complicated positions that don't resemble your opening of choice or have any themes that you can latch on to at all. Your book knowledge may not be very helpful there. It doesn't help much that this happens in just about every game of chess."

About what percentage of chess games have you witnessed? In how many of those did you have knowledge of what the players had been reading?

"It is important for club players to build up a suitable opening repertoire." - GM Artur Yusupov (2010)

"... [After 1 e4 e5 2 Nf3 Nc6 3 Bc4 Bc5 4 b4 Bxb4 5 c3, if] Black plays 5...Bc5 ..., White can play the desired 6 d4 with less risk. With [5...Ba5], Black pins the c3-pawn, thus not allowing White to take back with the c-pawn after 6 d4 exd4. ..." - FM Carsten Hansen (2010)
Could a comment like that be helpful to a player below 2000?

In chess it's easy to take for granted the things you've known for a long time.

Sounds like you wasted a lot of time memorizing opening lines.

Take a player who only studied _____ and knows nothing about openings, and suddenly the openings don't seem so unimportant.

Sure it could. What's the point?

Hardly. I know 5 or 6 moves in some positions and that's it. And even then it has nothing to do with the result of the game.