Questions about Y2/M01/game 3

I have questions about some moves or candidates moves that are not explained in the analysis proposed by ICS.
I wish to have some insights.



Here ICS points out Dvoretsky concept of superflous pieces, both knight and bishop (for white) are best placed on d4 but only one can fit there.

In the game Bb5 is played to get rid of knight in c6 that control that square, but then Nd4 move reduce bishop to passivity.

I don't understand why the variant in Ne5 exchanging knights and finally placing bishop on d4 is not good ?
White conserve bishops pair, in a fairly open game, this seems good to me, anyway Rybka considers it inferior (game variant is credited +0.30 while my continuation just earn a +0.00).



Later in the game we reach this position, where now the fight is about the isolated pawn.
I don't understand the purpose of Nc3 retreat ?

Of course it does attack the isolated pawn, but this is kind of a weak attack. Since this pawn is for now easily defendable, why not simply move the knight in the d4 outpost we have seen before (ICS says in year 1, when there is a pawn weakness, fix it with a knight, thus Nd4 is perfect, isn't it ?).

But more obviously why not just continue with Nxd6 Qxd6 Bc3 putting definitely pressure on this weak pawn, but also indirectly on b6 weak pawn if bishop relocate to d4 (again this key square) (as guessed, Rybka gives +0.20 for this line) ?

Superflous pieces? - I thought you could never be too rich or too thin.

Re. position 1, I don't think that after 14.Ne5 that Nxe5 makes sense as black really shouldn't do exchanges as the holder of the IQP. Rybka likes 14...Ne7; if 14....Bb7, and 15.Nxc6 Bx6, 16. Bd4? fails to the skewer 16....Ba4.

I agree, it makes ultimate sense to to exchange with 21.Nxd6, same reason as before.

After looking at the various lines for position 2, it seems that the 21.Nd4 isn't doing anything useful, and is ultimately blocking lines of attack to the IQP. Black is free to persue multiple strategies with the extra space and better piece coordination.

21.Nc3 it seems to do a nice job of restraining black queenside without the downsides of Nd4.

I just finished going over Lasker - Capablanca (10) 1921 in the month 7 tactical section. Comment is made that N at c3 plays a defensive role, defending the c-file. There is enough similiarity in the positions that it might be worth some time to review that lesson.

Yep, interesting idea additionally to attack the isolated pawn, it cut the 'c' file efficiently since pawn in b6 (nor obviously the isolated pawn) can annoy it, so that rook in Rc8 becomes misplaced or at least useless for a while.

Regarding Ne5 exchange, you are right, the exchange is not forced, thus such a move may not be as interesting as it seems.
Anyway even if the exchange is realized as indicated in the diagram, the final position still evaluates (Rybka) slightly less than the line played in the game, this puzzle me a bit since bishop pair looks attractive.
Maybe it's the loss of tempo that justifies it + the fact that Nc5 is a strong outpost, compared to the miserable situation of white light bishop who cannot relocate avantageously at this time (since black controls the key d3 square).

It appears to me that the difference is that with the Bb5 line played in the game the KR is brought into the game, whereas white has problems getting the rook into play in the Ne5 line of play.

In the termimal positon of the Ne5 line most of the engines seem to like 16...Qg5 after a couple of seconds which holds the white KB on the home square for a couple of moves. Naum in particular gives black a 0.2 CP advantage after ...Qg5 although all of the other engines show the position as equal.

So, as you point out, the white king bishop is a problem in the Ne5 line.

BTW, thanks for posting the position, it's very relevant to the month 7 stuff I'm working through a the moment.