11...e4 12.Bxg7 Kxg7 13.Nd4 f5 offers an impressive pawn diagonal that shuts in White fianchetto bishop. But after 134.h3 Ne5 15.f3, White starts to break it open again. That has implications for the future of Black's Q-side.

There was no other way I can see of Black's mobilising his Q-side. That White d-pawn, together with the fianchetto bishop is clamping a siege against Black's Q-wing. Come to think of it, it might have better a move ago if the OTHER knight had gone to d2.

I THINK the d2-knight wants to get to c4, to support the front line at d6. This pawn move puts a constraint upon Black's b-pawn, securing the c4-square for White.

Black might not be so very unhappy about that. The knight is now closer to d6. 14.Nc4 seems to be the logical follow-up to White's previous move.

It seems more in keeping. Maybe White plans something more ... erm ... forthright, involving a further advance of the a-pawn...? (No, I haven't looked... yet!)

Of course...

'Logical', in view of White's previous moves, seems 17.a5. But Black is already starting to equalise...

Black might have gained a tempo, here, with 17...Bf8 18.Bd5 Bb7. Even after 19.Bxf7+(?!) Kxf7 20... Re6 there is no defence for the d6-pawn.

18.Bxb7 seems to be indicated, ridding Black of one of his few active pieces. The strategic value of White's LSB seems to have depreciated, rather, in the last few moves.

OK, but White might have found 18...Bf8 pretty annoying...

A very fair assessment, methinks. Black has pried loose White's grip on the position. I rather suspect White underestimated the strategic strength - power and resilience both - of his d-pawn, and wrote it down too soon.