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17. Rab1 is a complete positional blunder. It does not only block White play at the queenside, it also weakens their grip on the center, expecially the a1-h8 diagonal.

Because of the gap at b4, White had to strenghten there position in the center by playing 17. Re1, but wait... that makes 12. Qf2 questionable as a correct approach (plan), because the Rf1-d1-e1 already lost a tempo. It actually loses 2 tempi considered 12. Qd1 had the option to answer Nxd3 with Qxd3 in contrast with Nxd3-cxd3 in the game. Because there is no second pawn at the d-file after Qd1-Qxd3 (compare: d3+d5), Rf1-d1 is positionally worse than having a Queen at d1 for White; there is already protection of d5 after 12. Qd1 and White still has the option to play Rf1-e1.

In other words: 12. Qd1 is a better square for the White Queen; it keeps the right tension on the center for White. White's pieces are well coordinated; they don't lose any tempi directed at building their central position in the game afaik.

Therefore White has a strong centered position after 12. Qd1:

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It's not hard to see why 17. Rab1 is wrong; White has to control e5: 17. Re1 cxd4 18. Bxd4 Rc4 19. e5 Qb4. 20. Rad1 Rfc8:

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Although White lost a tempo by playing Rf1-d1-e1 after 17. Re1, their pieces are working together. Black still has a lot to prove in this position.

So far the analysis with SF9.
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Now what says 17. Rab1 about the tactical aspects of the game for White? Obviously the Rb1 protects b2, but it also gets out of the a1-h8 diagonal. This is interesting, because when we go back at Judith's -crucial- 12. Qf2 decision and SF9's 12. Qd1 suggestion then it maybe worth to take another look at the position with SF9 and see what happens after an immediately 12. Ra1-b1

12. Rb1 e6 13. f5 Nd7 14. Bd2 Ne5 15. Qg3 c4 16. Be2 exf5 17. exf5 Nxc2 18. Qf4 gxf5 19. Qxf5 Qb6+ 20. Kh1 Ne3 21. Bxe3 Qxe3 22. Bh5 Qh6 23. b3 Rbe8:

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Again, Black has a significant advantage. Their pieces work well together as they are concentrated on the center. Concluded is the Ra1-b1 idea simply too slow for the position. Tactics flow for Black; White can't play 24. bxc4 Nxc4 25. Rxb7 Ne3:

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