Sagar-Kumaran, Chennai 2009. White played f4, and when Black went ahead with f5, White pressurized the c5 pawn with Nb3. When Black traded off that pawn, White pressurized the d6 pawn with Ba3 (which could have been used first on both pawns). In the end, White wound up with incredible play on the dark squares and a rampaging queen on g7.

I may well be looking at one of your games here, but I think the critical line might be 11.f4, trying to blast open the position.

I couldn't find an example of what I believe might be the critical line in my (admittedly slim) database.

About ten years ago, I was playing the Nimzo-Indian fairly regularly, and I encountered the following variation no less than three times:

1.d4 Nf6 2.c4 e6 3.Nc3 Bb4 4.e3 0-0 5.Bd3 c5 6.Nf3 Nc6 7.0-0 Bxc3 8.bxc3 d6 9.Nd2 e5 10.Rb1 Ne8

This is all a mystery to me: I can't for the life of me find my move 10...Ne8 in any of the literature—either recommended or otherwise. Christof Sielecki doesn't mention it. And I don't think Carsten Hansen does in his older book on 4.e3.

I don't pretend to argue that the move is especially good, but it doesn't strike me as bad. While a bit crude, it forces White's hand in the centre, as Black wants to expedite the ...f5 push. My results weren't too bad: +1, =1, -1, the draw and the loss coming against stronger opposition. I was comfortable in the draw, and managed to come completely off the rails in the loss. But does the move have any merit? Worth further investigation?