A little more unbalancing is (after 1.e4 e6 2.d4 d5 3.Nc3 Nxc3 4.Nxc3 Bd7 5.d5 cxd5 6.Qxd5 Nc6 7.Bg5) 7...f6!?, followed by either ...Ne7 kicking the queen (and heading to ....Ng6 if Qh5) or pushing on with ...f5, and then ...Nf6 again kicking the queen. Since Black can easily castle long soon, and since the White pieces are a little loose, ...f6 is not too weakening here, it seems to me.

Admittedly the pawn structure, in the long run, allows the exchange of heavy pieces on the central files. But the Fort Knox is not the Poison Pawn. To the White queen Black's d-pawn tastes a little sour at worst. I think that with 5.d5 White just gives up his long-lasting +/=, and no more severe punishment awaits him.

I fed 7...f6 to Rybka, which validated its tactical soundness and invented the witty ...f5 (after 7...f6 8.Be6). Then Black can aim for opposite-side castling, since White is pretty clearly going to go long.

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By the way, the variation of the Winawer to which talfan was referring above certainly exists, as I have played it many times. It is the branch of Alekhine's variation in which Black retreats the Bb5 to e7, then follows up with ...Nc6 preparing ...e5.  White then often answers ...e5 with d5, producing the structure in question. See for example Lillienthal-Botvinnik, Moscow 1936. Of course, Black's piece placement is fine there, whereas it is awkward, to say the least, in the proposed Fort Knox variation, which BPaulsen refuted pretty completely--though I don't think talfan (or anyone else) deserves to be humiliated for being wrong.

BPaulsen wrote on 06/16/10 at 17:03:50:

Guys, please keep up the good tone of communication. And if you think that someone is not right in his opinion, please provide some lines which prove your opinion. It is not a good shape to ask someone to be silent and not to post in the forum because he is not right or his analysis are wrong somehow. Everyone has the right to have his/her own opinion in some position or variation. But at the end concrete variations determine the final verdict on any line 

Hi all,

All of your ideas are really interesting. Personally, I feel that the move "e5" doesn't fit the spirit of the Fort Knox system. After all, the reason why Black wants to play the Fort Knox variation is because he wants a compact and solid set-up. The move "e5" seems to open up the position quite a bit and after the move Qh5, Black's position looks a little unsecured.

I think Mangler raised a very good point about the "clean equalizer" Bg4. I missed that move completely. Maybe the sequence " exd5, followed by Nc6" is playable after all. I will definitely give it a try.

Interestingly, someone played the same line against me yesterday. Like what BPaulsen said, the best way to counter such an unconventional move is to be unorthodox oneself. And that was exactly what I did.
1.e4 e6
2.d4 d5
3.Nc3 dxe4
4.Nxd4 Bd7
5.d5 
Instead of playing Qe7 as suggested in the forum, I attempted Qh4!?, attacking the seemingly weak e4 Knight. 
5.....Qh4
6.Qe2 Nf6
7.dxe6 Qxe4
8.exd7+ Nbxd7
And I got a rather comfortable game, albeit a little passive.
Although Black is very solid, it is rather passive and seems to lack counter-play i.e. no pawn break. Moreover, White has the bishop pair in an open position. I am not sure if the bizarre move Qh4 equalizes for Black, but I must admit that most of the winning chances must surely lie with White. Any thought?

Thank you all for your responses.

H-HH wrote on 06/16/10 at 14:02:31:


It's no great mystery that tactical threats come out of better positions, and all ...e5 did was give white the better position. Why do you persist in arguing in favor of a move you think is poor?!

The Winawer shouldn't even be mentioned - the positions there have zero in common with this one. There black gives up the bishop pair and space in order to battle against white's compromised structure. Unlike the Winawer, white's structure is totally healthy here.

Just as this position shouldn't be compared to typical Fort Knox lines, either.

H-HH wrote on 06/16/10 at 12:42:10:


So even you think ...e5 is mediocre now and obviously the Bd7 is in the way. It's not about the loss of tempo, it's about the fact it screws up black's piece coordination which is an issue when he has less space.

Did you really need to try to argue about it?

H-HH wrote on 06/15/10 at 21:02:40:


Check what I put in bolded letters from your last post - that's how I know what you're thinking.

White has a bigger space advantage after d5 being met by ...e5 than the Pd4 versus a Pe6. It's not a change in structure black desires. The problem is the idea itself, while playable (+=), doesn't attempt to challenge white's idea at all.

That's not even mentioning the concrete issue that white can pick up the bishop pair with 6. Qh5 if he so pleases (6...Bd6 is nearly forced, and white can play Nxd6 at will).

BPaulsen wrote on 06/15/10 at 17:20:25:


Don't know why do you know how I am thinking but then again since it will be harder to open the position the extra tempo should be of less significance, and not more. Also, white surely has a space advantage but not more than he had before.
Instead of demeaning my thought process could you please point out any flaws you think my suggestion had?

BPaulsen wrote on 06/15/10 at 14:47:36:


White already had a space advantage before 5.d5, and I don't think he gained much more with it. Of course Bd7 shall move agian, but so it is anyway in the normal variation, What black wants in the fort knox is easy development and rock solid position, albeit slight worse, and I still don't see what would refeute 5...e5. Of course I may be wrong, and 5...e5 may be poor, but I don't see yet.