I believe that 2...Nb8 is sound, but don't have the time to prove it.* And it doesn't seem urgent, since now 2...Ne5 looks OK. In the line 6.f4 ...9.0-0! there remain a few questions, and the PC gives White some advantage, but it is an unbalanced, difficult situation and should be playable. 

* If anyone, it is White who has to justify his wild play. 3.e4 (3.Nf3 f5) 3...e5 4.Nf3 Bd6! (introduced into master practice in Theresa Pohl - Sophie Greilich, German Ch. U10 Wittlich 2005) 5.Bd3 Nf6 6.0-0 0-0 7.c4 Re8 8.Nc3 a5. How can Black stand worse?

[quote author=27242E28490 link=1271505369/72#72 date=1273793663][quote]1.d4 Nc6 2.d5 Nb8 must be correct, e.g. 3.e4 Nf6 4.e5 Ng8 etc.[/quote]

This is a wild idea! (Which I remember from Myers' Nimzowitsch Defence book.) But how does Black go about equalising if 5 Nf3 then Nc3?  5 ...e6 maybe? -- I haven't quite seen the idea. Moreover (and more critically perhaps?), what does Black do against the 3 Nf3/4 c4/5 e4 plan intending Nc3, h3, Bd3? Zdenek's line looks interesting, but wasn't 11 a3? a big mistake?

In the 2 ...Ne5/5 Nc3 b6!? line: when I was looking at Crouch--Karpatchev the other day I thought 9 ...Bd6!? was maybe an improvement which made the line OK for Black, and the line you give seems OK to me too. But how do you deal with 6 Bf4 Ng6 7 Bg3 Bb7 (presumably) 8 h4? Off the top of my head I have three ideas: (1) 8 ...Bb4 (9 h5 Bc3); (2) 6 Bf4 Nc6!?; (3) 6 Bf4 Qf6 7 Qh5 Ng6 8 Bc7 Bb7 -- no idea yet whether this is enough![/quote]

2...Nb8 "must" be correct, since 1.e4 Nf6 2.e5 Ng8 is correct. It is unthinkable that the queen's pawn could achieve a thing which the king's pawn can't. 

5...b6. There are 13 games in the database. 6.Nf3 Nf7 7.Bc4 Bb7 8.Qe2 a6 9.Bb3 (Crouch - Karpatchev, Cappelle la Grande 1993). Yes, your 9...Bd6 looks fine. The PC also likes 8...Bb4 =. 

6.Bf4 Nf7! 7. Nf3 Bb4 8.Qd4 Bxc3+ 9.Qxc3 Qf6 10.Qxf6 Nxf6 11.e5 Nd5 12.Bg3 Bb7 13.0-0-0 Ne7 e.g. 14. Nd4 a6 (Riepe - Voss and Kessler - Voss, E-Mail 2003), almost =.

[b]6.f4(!) Ng6 [/b](6...Nf7 Audiffren - Labarthe, French Ch. [seniors] 2001; 7.Bd3! Bc5 8.Nf3 Bb7 9.Qe2) [b]7.Bd3 Bb7 8.Nf3 Bb4 [/b](8...Bc5) [b]9.0-0!? [/b](9.Bd2 Nf6 10.g3 Qe7 11.Qe2 0-0-0 12.a3 Bxc3 13.Bxc3 d6 14.a4 a5 15.0-0 e5 16.f5 Nf8 17.b4 d5) [b]9...Nf6 10.f5 exf5 11.exf5 Ne7 [/b]with an interesting situation (+=?).

1.d4 Nc6 2.d5 Nb8 must be correct, e.g. 3.e4 Nf6 4.e5 Ng8 etc. 

But I am more interested in 2...Ne5 3.e4 e6 4.dxe6 fxe6 5.Nc3. Now 5...b6 seems best: 6.f4 (6.Nf3 Nf7) 6...Ng6 7.h4 Bb7 8.h5 N6e7 9.Nf3 Nc6 10.a3! (10.Be3 Bb4) 10...Qe7 11.Be3 0-0-0 and Black has a sound position, e.g. 12.Qd2 Nf6 13.0-0-0 Qe8 14.e5 Ng4 15.Bd3 d6 =.

Hi linksspringer,
Yes, I remember it well! The thread was this one, where the line relevant to the 2 d5 Nb8!? Bogo is discussed in the first few posts:

http://www.chesspub.com/cgi-bin/yabb2/YaBB.pl?num=1209474437/2#2

As a summary, we looked at Wirthensohn--Herzog, "Europe"(!) 1993, as a key game (Berdichevsky game 306, p. 164). It went 1 d4 Nc6 2 Nf3 d6 3 d5 Nb8 4 c4 g6 5 e4 Nf6 6 Nc3 Bg7 7 h3 0-0 8 Bd3 c6 9 0-0 a6 10 Re1 b5 11 cb ab 12 dc b4, unclear. B. gives Black's 10th move an exclamation mark, but we felt that 11 Bf4! is good for White.

I'm looking forward to taking a look at this again. Can Black usefully avoid this line after 1 d4 Nc6 2 d5 Nb8, or if not can he improve on it? I've a faint memory that after our original posts I looked at a line for Black involving ...Nfd7, ...Na6 and ...N(one or the other!) c5 and thought it not too bad, but I need to have a rummage through my notes ...

[b]Edit. [/b]But thus far, I have to say, Black's plan of simply surrendering two tempi is looking pretty ropy!

SWJediKnight,

Personally I think the Nimzowitsch Defence is just fine (see the several threads!), but be that as it may, it has surely enjoyed a much better reputation than the Bogo, esp. with Miles championing it! We have to remember that Burgess went so far as to attach a '?!' sign to ...fxe6 in the Bogo!

@ Stefan -- I thought I saw a few potential problems with the ...fxe6/...a6 idea too -- but there's still 3 ...Ng6!?.

And yes, there's still 2 ...Nb8!? too! I remember discussing this a few years ago with linksspringer -- will try to relocate the thread when I get a minute. I seem to recall us tentatively concluding that Black wasn't quite all right against a standard c4/e4 plan, but I've every confidence there's loads still to be discovered in these lines!

I think the Bogo has probably been neglected/frowned upon for two main reasons:

1.  It allows transposition to the Nimzowitsch Defence with 2.e4, and that system doesn't enjoy the best of reputations (though I personally think it's better than its reputation, with both 2...d5 and 2...e5 probably conceding just a small edge)

2.  It violates the principle "don't block the c-pawn in queen's pawn openings" which probably also contributed to the neglect of the Chigorin Defence to the Queen's Gambit in the past.

I remember reading in Chess Monthly that Tony Miles only ever faced 1.d4 Nc6 2.d5 once, in a simultaneous game.  Thus, I don't think 2.d5 was traditionally the objection in his time, or else some GMs would have tried it against him.

linksspringer wrote on 05/08/10 at 12:46:47:

4...dxe6 5.Qxd8+ Kxd8 isn't attractive for Black. I'd prefer 4...fxe6 5.Nc3 a6 6.f4 (or 6.Nf3 Nxf3+ 7.Qxf3 Qf6 intending d6, Ne7, Qf7 etc., about =) 6....Nf7 7.Nf3 b5, about =.