Annotated Game #203: Small advantages are hard

This next tournament game illustrates the difficulty of doing meaningful things with small deviations from theory which, while not best, aren't bad in themselves.  My opponent clearly did not have a familiarity with the Caro-Kann, so I easily achieve equality and perhaps a slight positional edge, but no more.  Some patient re-deployment of my pieces was likely the best strategy, but instead I let my opponent gain a slight initiative on the queenside and then achieve a nice positional plus in an imbalanced position.  However, he did not see the critical continuation on move 27, which would have involved shifting his queen to attack my bare kingside, and we ended up in a repetition of moves.  He played well, so I have no regrets about the result, despite the large rating gap.

A more general strategic insight is that against significantly lower-rated opponents, if you have a more imbalancing opening repertoire, you probably will have greater chance of success.  I don't think that's a reason to give up playing solid openings like the Caro-Kann if you are higher rated, but it is a consideration if you want to create more obvious winning chances.

[Event "?"]
[Site "?"]
[Date "????.??.??"]
[Round "?"]
[White "Class D"]
[Black "ChessAdmin"]
[Result "1/2-1/2"]
[ECO "B13"]
[Annotator "ChessAdmin/Komodo 11.2"]
[PlyCount "58"]

{B13: Caro-Kann: Exchange Variation and Panov-Botvinnik Attack} 1. e4 c6 2. d4
d5 3. exd5 cxd5 4. Nc3 {this is one of those moves that is unusual in the
opening, but not necessarily terrible. We are now out of book.} Nf6 5. h3 {
preventing ...Bg4, but perhaps not the best use of a tempo this early.} Nc6 6.
Be3 {Again maybe not the best, but a sensible reinforcement of d4.} Bf5 7. Bd3
Bxd3 {the usual practice in the Caro-Kann is to exchange bishops on d3 when
White offers the trade. This does develop White's queen, but it is usually
preferable to having it be exchanged on g6, which then provides more of a
target for any kingside advances by White.} 8. cxd3 {although the doubled
pawns look awkward, Komodo evaluates it as equal to the queen recapture. The
pawns could be weak at some point later, but are hard to attack. And as
compensation, White now contests e4 and c4, so a Black knight can no longer go
to those squares.} e6 9. a3 {covering b4 and further restricting my knight.}
Be7 $11 {a rather passive bishop development.} (9... Bd6 {I had not played due
to the possible harassment by White's knight, but the engine evaluates that as
being better for Black:} 10. Nb5 Bb8 $15 {and now the knight cannot stay on b5,
while the bishop will have a good diagonal permanently. Black will need to
spend some time re-deploying his pieces, but there is no hurry as White has no
threats.}) 10. Nf3 O-O 11. O-O Rc8 {the opening phase is over and the position
is very balanced.} 12. Rc1 a6 {Controls b5} (12... Ne8 13. b4 a6 {followed by .
..Nd6 is Komodo's suggested plan, repositioning the knight to a better square
and freeing f6 for potential use by the bishop. This would also have avoided
some of the coming awkwardness on the queenside.}) 13. Ne5 Nd7 14. Nxd7 {
My opponent's strategy is evidently to exchange off pieces and head for a draw.
} (14. Nxc6 {might be a better choice for exchanging down.} Rxc6 15. Na4 Rxc1
16. Qxc1 $11) 14... Qxd7 15. Na4 {threatening a fork on b6.} Qd8 16. Nc5 {
now the knight is attacking b7, forcing me to respond.} Bxc5 {here a bit of
patience and boldness might have served me better.} (16... Qc7 $5 {places the
queen opposite the Rc1, but there's no way White can take advantage of this.}
17. Qb3 Bf6 $11 {counterattacking d4 rather than trying to defend b7.}) 17.
dxc5 d4 {I thought for a while here on how would be best to proceed.} (17... e5
{is perhaps the more natural move here, although the text move is just as
equal.}) 18. Bd2 Qd5 19. Re1 a5 (19... Rfe8 $5 {is just as equal as most moves
here, but it has the advantage of activating the rook and reinforcing Black's
possibilities for central play.}) 20. b4 axb4 21. axb4 {by now we have a clear
imbalance in the position between the 2-1 queenside majority for White and
Black's central pawn majority. It's still dead even in terms of evaluation,
however, as neither side has a way to make real progress with good play. In
practice, however, White's more advanced pawn majority creates more pressure,
as we'll soon see.} Ra8 22. Ra1 Ra2 23. Rxa2 Qxa2 24. b5 Ne7 $6 {the first
real miscalculation on either side.} (24... Na7 {threatening the b-pawn is
much more effective as a defense.} 25. Bf4 Qa5 26. Qa1 Qxa1 27. Rxa1 Nxb5 28.
Kf1 $11) 25. Bf4 $14 Nd5 {the knight looks good visually, perhaps, but now
White gains a significant positional bonus by installing his bishop on d6.} 26.
Bd6 Ra8 {this looks logical, but White could now take advantage of the rook's
absence from the kingside by targeting e6 with a sacrifice.} (26... Re8 $5) 27.
Qb1 {this leads to a drawing line.} (27. Qg4 $5 {is critical. In addition to a
potential sac on e6, there is a brute force threat against Black's king after
Be5. The best defense according to the engine is to pitch the h-pawn as a
distraction.} h5 28. Qxh5 Qd2 $16) 27... Qd2 28. Rd1 Qe2 29. Re1 $11 Qd2 {
the position was objectively equal and I felt White had the only real winning
chances if I deviated, so I was content to take the draw.} 1/2-1/2