I used to play the following as my main defence to 1.d4

1 d4 e6 2 c4 c5 3 d5 exd5 4 cxd5 d6 5 Nc3 g6 6.e4 Bg7 - the point being to play Ne7 and f5 - there was a NIC survey on this line back in 1997 I think.

7 f4 doesn't quite work although it can be messy.  I once had a game (against someone rating 2260 ish) that continued 7...Ne7 8.Nf3 O-O 9.Be2 f5 10.e5 dxe5 11 Ng5 Nb6 12. Qb3+ Kh8 13.Nf7+ Rxf7 14. Qxf7 e4 15.Be3 Nd4 with a fair amount of comp.  I won in around 20-25 moves after gaining some time against the white Qf7. Against 8.Bb5+ Nd7 9. a4 O-O 10.Nf3 f5!? 11 Ng5 Bxc3+!? 12 bxc3 fxe4 is one of several lines that work.

I won quite a few other games but had a few disasters - however I should point out that if you play the Bd3/h3 system then 7.Bd3 is prob best (7.Nf3 a6 7.a4 Bg4!? tries to transpose to the anti-classical lines.  If black persists in playing 7...Ne7 then 8.h4! can be strong.  However if white doesn't do this...

1.d4 e6 2.c4 c5 3.d5 exd5 4.cxd5 d6 5.Nc3 g6 6.e4 Bg7 7.Nf3 a6 8.a4 Ne7 9.
Bd3 O-O 10.h3 h6 11.O-O f5 12.exf5 Nxf5 13.Be2 Nh4 14.Be3 Nd7 15.Qd2 Nxf3+
16.Bxf3 Rxf3 17.gxf3 Ne5 18.Kg2 Bxh3+ 19.Kxh3 Nxf3 20.Qe2 Qh4+ 21.Kg2 Qg4+
0-1

Is another fun game of mine.

A messy one:

1.d4 e6 2.c4 c5 3.d5 exd5 4.cxd5 d6 5.Nc3 g6 6.Nf3 Bg7 7.e4 a6 8.a4 Ne7 9.
Bd3 O-O 10.O-O h6 11.Bf4 f5 12.Bc2 fxe4 13.Qd2 exf3 14.Bxh6 fxg2 15.Rfe1 
Nf5 16.Bxf5 Rxf5 17.Bxg7 Kxg7 18.Ne4 b6 19.Ra3 Ra7 20.Rh3 Rh5 21.Qc3+ Kf7 
22.Rxh5 gxh5 23.Qf3+ Kg8 24.Nf6+ Kg7 25.Nxh5+ Kh8 26.Nf6 Re7 27.Qh5+ Kg7 
28.Qg5+ Kf7 29.Ne4 Ke8 30.Qg6+ Kf8 31.Qh6+ Kg8 32.Qg5+ Kf8 33.Qh6+ 1/2-1/2



The advantage to this move order is that:

1) The f4 systems are perhaps not quite so dangerous as before.  Still messy and dangerous but I'd rather be black from a practical point of view.
2) More generally can get a non-theoretical benoni

Disadvantages:

1) it doesn't really avoid the Bd3/h3 system.  I played 7.Bd3 Ne7 folloed by f5 a few times (see above) but 8.h4 puts me off slightly now.

2) you need to be prepped for 2 e4 and 2 Nf3 as well.  1 d4 c5 2 d5 e6 3 e4 gives white excellent chances for a pain free edge.

3) If white plays quietly (e.g. fianchetto lines) I think you just had to transpose to the normal MB.  I think that Bf4 systems can also be even more dangerous here.

You are right, i mean 1.d4 g6 2.c4 Bg7 3.Nc3 c5 4.d5 d6 5.e4 e6 6.f4 exd5 7.cxd5 a6 8.a4 f5

The idea is a rapid f5 for exemple : 1.d4 g6 2.c4 Bg7 3.Nc3 c5 4.d5 d6 5.e4 e6 6.f4 exd5 7.cxd5 a6 8.a4 Ne7  9.Nf3 f5!?

What do you think of the line : 1.d4 c5 2.d5 e6 3.c4 exd 4.cxd d6 5.e4 g6 6.Nc3 a6 7.a4 Bg7 with the idea Cge7 or Cgh6 ? have you seen serious analysis or played games with it ?