Done. Only half finished really since there is a lot to look into. Rad1 was an interesting find aswell as Bc4.
To the game: http://www.chess.com/votechess/game.html?id=14051
To the Alliance: http://www.chess.com/groups/forumview/move-28-the-conditional-move-thread?
Following Kotov's advice (A. Kotov,1913-1981, http://en.wikipedia.org/wiki/Alexander_Kotov) to always look at a new position with the beginner's eye. I don't know if that is the phrase in the English translation of Think Like A Grandmaster but it is good advice. He also talked about sitting on your hands and write down the move on the score sheet before executing it. His observation was that hasty moves often were mistaken ones. It is no longer allowed to write down moves beforehand according to the Fide ruling but Kotov's advice still holds good.
"26. ... Rb8 27.Be2 (Threat:Bxa6) Rc6 28.Rb4 Bd8 29.Qd5 (Threat:Qxe5)(29.Qa4 (Threat:Bxa6) Rbc8) and the Black Queen must move. Some interesting pressure play here. White is expanding her area of influence, so besides keeping Black busy on the queen wing something is slowly building up against the king side. Just think Bc4 and Rd1-d3-f3." ( Comment move 26 )
" ... and the candidates are:"
28.Rb4 has been the "main line" for a while, so I'm not looking into that now but looking for other possibilities.
28.Bc4 Can be a direct way of putting pressure simultanously on f7/b7 via Bd5. If Black goes for the a-pawn, what happens? 28. ... Bd8 29.Bd5 Rc5 30.Rda1 Qc7 31.Rb4 Rxa5 32.Rxa5 Qxa5 33.Bxf7+ Kh8 Since there are pieces in play the king is probably safest in the corner. Now the white king is threatened as Qa1 is mate. 34.Ra4 The queen must move. The endgame for Black is somewhat inferior now because the second player has three pawn islands and White only two, the backward pawns at b7 and d6 are still vulnerable and the king is decentered. On the other hand, Black can try the other resource and push b5. 28. ... b5 Now White can choose between moving the bishop or taking the pawn e.p. A) 29.Bd5 Rc7 (bxa4 Qxb8 and White will probably end a pawn up) 30.Raa1 and the queen wing is sealed. I don't know if this is good for Black. One plan here for White is to switch a king side mobilization, forcing the Black troops there and the turn back to the queen side. Black has less space and will be slower in regrouping. By shuttling between the wings White might create more weakspots and eventually Black can't keep up with the pace. B) 29.axb6 ep Rcxb6 (Rbxb6 The queen retreats and a6 will be hard to defend) 30.Rb4 Rxb4 31.cxb4 Black might loose both the d6 and a6 and still hold, so I dont judge this as satisfactory for White. Well, Bc4 was interesting enough for a diagram.
28.Qd5 Invites the temporary sac Rxc3 29.bxc3 Qxa4 30.Qxd6 and White can gain yet a pawn but it is a passing thing since c3 and a5 are weak. Black is also out of the cage so it does not look too promising.
28.Rc4 What if Black just trades? ... Rxc4 29.Bxc4 The old Bxa6 is at play again so Rb8 needs to move or a guard. ... Qc7 30.Rd3! The rook is heading for f7. ... Bf6 Blocking access to f7.
28.g3 A possible waiting move. It is committing and the 3rd rank gets clustered if for instance Rd3-h3.
28.h3 A possible waiting move. It is committing and the 3rd rank gets clustered if for instance Rd3-h3.
28.Kf1 A bit too early I think to bring the king into play.
28.Bd3 I don't really see a point with this. White is after the a2-g8 diagonal, it's easier with Bc4 and then eventually regroup Q/B.
28.Rd5 Guarding the problem child a5. It also takes the edge out of the counter b5 28. ... b5 29.c4!
28.Qa3 is a prophylactic move aimed at the push b5, which wont work now.
28.Qa2 is a prophylactic move aimed at the push b5, which wont work now.
28.Rd3 only disorient the white pieces, it's too early to turn to the king side.
28.Rad1 is a move I haven't considered before. It looks usefull though. It takes some heat of a5 in a better way than Rd5, since that move clutters the view of Q and B. Rad1 still guards the back rank and brings down fire on the a-file if b5 were played. 28. ... Bd8 29.Rb4 g6 There isn't any other useful moves I can see. 30.Bc4 Kg7 31.Bd5 Using the least expensive piece to effectively block d6 and putting preassure on f7 and b7. 31. ... Rc7 32.Rb6 This is a nice White setup. What if 28. ...b5? 29.c4! wrecking the black queen side.
Phew! White certainly has a lot of options, especially compared to Black, who walks a thin line.
Well, this is by no way exhaustive. Analyses on 28.Rb4 can be found elsewhere, on these pages, at the Alliance and in the main forum. I still have Rc4 to look at and some of the other candidates are only sketched but it will not be today, if ever before Natalia makes her move. I find Bc4 more attractive but it may be a matter of taste and style. That move is not as easily neutralized as Rb4 seems to be although White keeps the edge there also.
Rda1 starts to look interesting though.