There is lot of interesting responses tonight!!
I will try to respond to some of the questions or remarks.
Quote:19.Ba2 can lead to interesting complications:
a) 19...Rxd4 20.Rde1
a1) 20...Nc4 21.Bc3 Ne5 22.Qf2 looks good for White.
a2) 20...Bxh2 is interesting: 21.Qf2 Be5 22.c3 Rxd2 23.Nxd2 Nd7 24.Ne4 Bc7 and Black can think of ...f5 again.
a3) 20...Rdd8 21.Bxa5 Nd5 22.Bd2 Bxh2 23.c4 Qc7 24.cxd5 cxd5+ 25.Nc3 d4 26.Bxe6+ unclear.
I think 19.Ba2 is a little more precise than 19.Bb3 against 19..Rxd4 because Black have not the interesting move a4!?with gain of tempo here, but I think 19..Nd5(!) could be the best move, with the idea to do put a piece on f4 with somes exchanges. And by comparison with 19.Bb3 in this position, I prefer the bishop on b3.
Quote:Markovich wrote on 26-7: "Play solid moves; eschew the second pawn." That is a strong argument to prefer 10.Nxg6 hxg6 11.Bd3. Black can reach safe equality though with Qxd4 12.Rf1 Qh4+ 13.Kd1 f5 14.gxf6 gxf6 15.Bxg6+ Kd8 returning the pawns.
After 13..f5 I would rather prefer White here, where your king is quite dangerously placed, and mine will castle long. 13..Bc5 could be the best move, as I have already analysed for my own new theory but I will keep it secret for an eventual new match against Markovich in this line.
Quote:Another intriguing question is, if Black wants the white pawn on h2 or on h3:
5...Bg4 6.h3 Bh5 7.g4 Bg6 8.Ne5 e6 9.Qf3 c6 (there are many, many deviations) 10.g5 Nh5 11.Be3 (11.Nxg6 hxg6 12.Bd3 Qxd4 13.Rf1 and Qe5+ is a disruptive check) Nd7 12.Nxg6 hxg6 and if both players follow the game, after 24...Qf4 (in the game 23...Qf4) Black is better, as there is no check on h3! I have not found deviations for White from move 10, using the pawn on h3 to his benefit.
Does this mean, that 5...Bg4 is more precise than 5...Bf5 ?
That's a very interesting question that I had too, where I gave somes of my ideas in this thread the 07/08
There is a copy and past from a part of what I have said that day :
But Leisebein played this position a few times like this :
1.d4 Nf6 2.f3 d5 3.e4 dxe4 4.Nc3 exf3 5.Nf3 Bg4 6.h3 Bh5 7.g4 Bg6 8.Ne5 e6 9.Qf3 c6 10.g5 Nh5 11.Bd3 Qxd4 12.Nxg6 fxg6 13.Be3 Qh4+ 14.Kd2 Ng3 15.Rhg1 Bd6 16.Qg4 Qxg4 17.hxg4 O-O 18.Rg2 Nd7 19.Rag1 where the games finished with a draw.
The good point for Black of this similar way of play with the pawn on h2 is that White couln't put the queen on g4 here but g3 isn't an hole here. Of course it's still an interesting question I think. So, ok there is an hole in g3 compared with the same position with the pawn on h2, but it has the advantage of the Qg4! move in somes position, like in the possible main line that Leisebein have played a few times. For this reason, White should not fear fxg6 with the pawn on h3, compared with the pawn on h2. But the final conclusion of which of pawn on h2 or h3 is better, is still unclear. All depend of the presice continuation. Effectively, if the pawn was on h3 now instead of h2 in our actual game, it would favour Black here, but I wouldn't have playing in this way too.
Quote:On the 10.Nxg6 hxg6 11.Bd3 line:
I actually think 10.Bd3 is stronger (despite the ...fxg6 resource) because after 10.Nxg6 hxg6 11.Bd3, I think 11...Be7! is a strong move.
If White would have nothing to fear about fxg6, then, the move order 10.Bd3! Qxd4 11.Ng6 hxg6 would be the most precise because it's more forceful like you have pointed out. But in my move order to avoid fxg6 after 10.Nxg6 hxg6 11.Bd3; ok Qxd4 isn't forced either, but I don't think 11..Be7 is too dangerous, after 12.0-0 I reach the type of position that I wanted for. I prefer to let 11..Be7 possible than hxg6.
Quote:Question: in the actual game, was there something against 16...e5 ?
Yes, 16..e5?! 17.d5! cxd5 18.Nc3 e4 19.Nxd5 exf3 20.Nxe7, etc, and White are better.