@ NeverGiveUp
Having mentioned Victor Moskalenko's "Revolutionize Your Chess - A Brand-New System To Become A Better Player" (New In Chess, 2009) in another thread, it came to my mind that this book could be of your help about studying your favourite Nimzo Indian's Saemish/Kmoch variations.
More than 50 pages of good analyses sharing many ideas for white from his own experience. 

I had this theme as a variation in a game, indeed White must have played f3-f4-e4-e5 and Black b6-Ba6-Nc6-Na5. 
The quickest route may be 1.d4 Nf6 2.c4 e6 3.Nc3 Bb4 4.f3 0-0 5.a3 Bxc3 6.bxc3 Ne8 7.e4 b6 8.Bd3 Ba6 9.f4 Nc6 10.Nf3 Na5 11.e5 (see diagram).  

Now 11...Bxc4 12.Bxh7+ Kxh7 13.Ng5+ Kg8 14.Qh5 Bd3 is the theme. Here it should work, as Black seems to defend after 15.f5 Bxf5 16.0-0 Bg6 17.Qh4 f6 18.Rf3 fxg5 19.Rxf8+ Kxf8 20.Bxg5 Qc8 21.Rf1+ Kg8 22.Be7 Bf5 23.g4 d6 (by following chessok.com online opening tree, Black lost horribly in Brasket-Bisguier, Puerto Rico 1968, by playing 20...Qxg5, perhaps somebody can post the game). 
All in all, a risky but useful theme to remember, methinks.

as for (b), I don't know if a theoretical verdict can be found, but it's popular for good reason, since White gives a pawn and (more importantly) Black's  ...Bxc4 attacks the bishop and sometimes allows for Bxh7+ Kxh7 Ng5+ Kg8 Qh5 Bd3 (a funny theme). Still it's pawn vs attack, perhaps easier to play for Black between same-strength players, but not easy to draw a conclusion.
If you want to play with f3 and a3, isn't it better to start with f3 ? you typically wait for Black to castle or play d5, and then you can play a3, now Bg5 is a threat and Black often has to play Nh5 or Ne8, in fact Black's ...0-0 is good for your attack. Just practical tips, certainly Vass or other people will have more accurate views.

Spot on again Vass - 8. ... e5! is a very good move. In several variations the rook an a2 is seriously exposed after this. So my conclusion is that this variation is not very good for white.

NeverGiveUp wrote on 09/19/11 at 09:49:41:


Further on this guys - a club mate of mine has now suggested the clever 8.Ra2!? instead of Rb1. At first sight this looks like an even more nonsense move than Rb1 - but consider that Ra2 is a perfectly normal move in the Saemisch: to mobilse the Ra1 and to be able to transfer it to the center or kings side. Again after the natural 9. ...b6 white continues 10.e4! Ne8 (cd4: 11.cd4: Nd4:?? 12.e5 Ne8 13.Be4 +-) 11.Nf3! and white is well placed with the knight on f3. After, say 11. ... d6 play may continue either with 12.e5!? or 12.Be3 e5 13.d5, when the natural Na5 can be met with Nd2.

According to Amazon, coming in March 2012:

The Strategic Nimzo-Indian:  A Complete Guide to the Rubinstein and Saemisch Variation by Ivan Sokolov

You just need to be patient.   

Lee Roth wrote:
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In that Saidy-Unzicker line, what do you do after 7..Nxd5?
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1. d4 Nf6 2. c4 e6 3. Nc3 Bb4 4. e3 O-O 5. Nge2 d5 6. a3 Be7 7. cxd5..
Good question! This 7...Nxd5!? is a very serious try for equality. I myself played it with black in four or five of my OTB games. And I never played it with white.. Anyway, it seems one of my opponents knowing that I play Nimzo has been prepared a line in which I struggled very much. This game which is not pleasant for me to remember continued: 8.Bd2! Nd7 9.Qc2! (my marks) not trying to expand with e3-e4 or playing g2-g3 and Bf1-g2 right away. In my analysis after the game I've found I made a dubious move 9...N5f6?! which was the main move at that time. There are several moves for black here, of course.. I suppose 9...N7f6!? is the most appealing. But my feeling that something is not quite good for black here stayed for a long time. After that game I never played 7...Nd5 anymore. Not because it's not good, but because it's difficult to handle in an OTB game. All I can say for this line is that after 8.Bd2, 9.Qc2, Rc1 or Rd1 (if c7-c5) and e3-e4 in the right time white is having at least a minimal edge. One thing I'm sure of is that 9....N5f6 is not good. 
Edit: I remember Angus Dunnington in his excellent "The Nimzo-Indian Rubinstein - The Ever-Popular Main Lines With 4.e3" (2003) explained very well all the problems that white and black can face after 7....Nxd5. I think he recomended this 8.Bd2, too..

Markovich wrote on 09/20/11 at 16:49:16:


You may be right.  But, I have wonder about the following very common sequence:

1 d4 Nf6 2 c4 e6 3 Nc3 Bb4 4 e3 c5 5 Bd3 Nc6 6 Nf3 Bxc3 7 bxc3 d6 8 0-0 e5 9 Nd2 0-0 and now 10 Rb1 b6 is pretty much the main line.

NeverGiveUp's line has lost a tempo with a3, but on the plus side he can happily play Ne2 instead of Nf3 which is supposed to be good vs the Huebner.  But I confess this line isn't in my repertoire for either side, so I don't know all the subtleties...