The Qatar Masters Open held in Doha, was a 9-round Swiss and had 92 GMs out of 154 players. The participants included former World Champion Vladimir Kramnik, who was playing in an Open tournament after 22 years, Dutch GM Anish Giri, the tournament's top seed, and Azerbaijani GM Shakriyar Mamedyarov which who the top three seeds. The tournament was won by Chinese GM Yangyi Yu who just three months before had made it into the final four in the Millionaire Chess Open but failed to advance to the finals after losing from a won position. Shankland scored +3 -0 =6 finishing 11th with a performance rating of 2734.
In his game against Guseinov, Shankland won the game before it even started thanks to his team of seconds ferreting out the position's secrets in home analysis using Stockfish. Shankland had assigned one of his seconds to analyze moves to play against the Dragon Variation and during one of his weekly conference calls, they presented him with potential novelties. Then Shankland memorized the lines that Stockfish had discovered. Of course Shankland didn't know what his opponent would play, but the Accelerated Dragon was one of his favorites, so there was a good possibility it would come up.
Grandmasters not only research their opponents’ preferred opening lines, but run statistics on various positions they’ve played to identify their stylistic tendencies and flaws.
In Shankland's case, at the end of 2013 he put together a group of ambitious young players to do opening work with him and divided the assignments so nobody would be working on the same thing at the same time. It was old security maxims at work...everything on a need to know basis and keep the "cells" divided so nobody has the big picture.
Using this method Shankland had people he could trust and who were good enough to meet his high standards of analysis. Shankland discovered something with this method: finding good moves had less to do with playing strength and more to do with ambition and work ethic. This showed up in this game where he crushed a 2600+ opponent straight out of the opening using analysis that came from one of his second's laptop.
Shankland emphasized that this proves how it is important to be well prepared in the opening because when you play against a strong opponent, opening preparation exerts a strong influence on the final result. Of course top level correspondence players have long been aware of this. These days all top level CC player emphasize the importance of opening preparation.
Top players, both OTB and correspondence, use 90-95 percent of their training time on opening preparation. Of course we rating-challenged folks shouldn't go that route. The truth is, these days a correspondence player can't even rely on opening books that come with chess programs. Those books are made up from a database of games by human players, including weak ones. Top players make their own books. Somebody, Alekhine maybe, when informed that a move was not "theory" was supposed to have replied, "I am theory!"
In Grandmaster play, if you can't neutralize an opponent's preparation, you will probably be in big trouble like Guseinov.
Beside GM Alex Yermolinsky who in his Road to Chess Improvement recommended studying mainline solid openings, it's also the recommendation of GM Igor Smirnov whose advice is don’t play dubious openings. He wasn't talking about the Grob Attack! He was talking about openings like the King’s Gambit, the Center Gambit, Bird’s Opening, etc. Like Yermolinksy, he says that if your opening is not good, then sooner or later, better opponents will make it unpleasant, you will start getting into trouble and losing.
His advice: you should play normal openings, which correspond to the basic strategic ideas. Then you don't have to worry too much because no one can refute correct openings.
How do you know if an opening line is good? Use a database and see how many players over 2600 play it. Chances are good that they have checked it out with an engine, but as Shankland shows, even then, there may be room for further improvement.
In his game, the fact that Shankland was moving quickly was no doubt a sure sign to his opponent that home analysis was involved. When that happens nerves start to take their toll, too. But, one thing that the one facing home analysis must not do is try to find some strange move hoping to break his opponent’s preparation. They have to be very careful.
The Chessbase database contains the game MacKenzie Molnar vs. Eugene Perelshteyn that was played in the US Chess League the same year. It was probably that game that the seconds were analyzing when Stockfish came up with the "innovation" 13.a3. Its evaluation after Molnar's 13.Qd3 was in favor of white by 0.27. After its preferred 13.a3 the evaluation nearly doubled to half a Pawn. If you're a GM, I guess that's worth investigating.
If you think you are facing a prepared variation or a booked up opponent it's usually best to avoid going into a tactical situation at all costs because it's very likely that his engine analysis has prepared him for all those tricks.
All that said, Grandmasters are successful (sometimes) in finding these obscure positional nuances because of their superior strategic understanding. Opening preparation is extremely important, an art in modern chess. And because it's mostly about strategy, it makes modern chess boring.
Here's my take on all this advice. This is all good, sound advice if you're a kid aspiring to become a master. For the rest of who have little hope of improving and are just playing chess for fun, it's a boatload of hype. Play whatever opening you want and have fun.
In the following online G15 I played the long discredited Danish Gambit which soon fizzled out to nothing...a dead drawn four Rook ending which my opponent managed to lose and so it's somewhat instructive.
While seeking out some information on double Rook endings I discovered the following sites that offer some good instruction:
Rook Endings in Theory at Exeter Chess Club
Double Rook Endings at Chessburst
Tarrasch Rule at Wikipedia