Ive just done some research on chessbase's online database and some further thoughts have occurred to me. Firstly Blehm-Pavel certainly does seem like a good illustration of White's chances, however there is the game Kveinys-Matlak, played towards the end of 2002 which seems to improve for Black:

16. Ng3 Nxg3 17. hxg3 Rf6 (!) 18. Qd2 Be8 19. g4 (perhaps this is the mistake) Bg6 20. Bxg6 Rxg6 21. g5 h6 22. gxh6 Rxh6 23. Rad1 Rf8 24. Qe3 Qc7 when Black seems to have good play for his weak pawns and drew shortly.

Obviously there may be room for improvement here but Black's plan of Be8-g6 looks reasonable.

Secondly in the line covered by Jon Rorosgard with Bxe4, I would like to draw people's attention to the game Anka-Reilin in which White won with remarkable ease. Everyone seems to play 18. Nxe4 but Anka played 18. Qd2 (!?). Unfortunately Black was much lower rated and didn't respond well at all, but this move looks good.

I offer the following basic analysis:

as in the game 18. ... e5 (?!) 19. dxe5 Bf5 20. Qc2!? Nxe5 21. Ng3 and White looks to be better

18. ...  Bc8!? opening up the rook looks interesting: 19. Qc2 side-stepping the rook seems best Nxd4 20. Qxe4 and White seems to have a fairly standard position with good chances against the isolated pawns

18. ... Rf5! (found by Crafty) seems to be the solution, and quite a nice visual move. 19. Rad1 e5! and Black seems to have a nice position.

So Bxe4 doesn't seem to be the way forwards, but White needs an improvement against Matlak's line!

Jon,

15...Bd7 is certainly playable - indeed my database shows that black actually scores reasonably with it (most games end in draws, although almost invariably black is the higher rated player) - however I believe white should be a bit better after 16.Ng3 Nxg3 17.hxg3. Obviously black is not a lot worse here, however there is no reason why white should not be able to press for the full point: he is well developed and possesses the better bishop and a grip on the dark squares.

For a good example of how to exploit these small advantages, take a look at the game Blehm - Szymanski 1999.

All the best,

Eddie.

I am new to the forum. My name is Edward Dearing and I am an IM (elect) from Scotland, but don't really play much chess these days due to university commitments. 

I used to play the Qb6 line with black, and in fact gave it up (before any of the games you have mentioned were played) because I concluded that the position after 12.b3 is just very difficult for black.

Your observation that 14...Ne4 15.Ne2 Rxf3 16.gxf3 Ng5 is thematic is correct, indeed I recall spending some time analysing it. However I would not attribute too much to the fact that black drew quickly in this game: Summerscale is a 2500+ GM, was 100 points higher rated than his opponent, and has since switched systems to 3...c5 against the Tarrasch. Indeed I believe that there are several improvements for white: in the first place white does not have to play 17.Kh1. Two earlier games (Acs - Schneider 1995 & Seger - Rechel 2000) continued 17.f4 Nf3+ 18.Kg2 Nfxd4 19.Re1/Rc1 and in both cases white was able to stabilise the center and gradually exploit his material advantage.

On a similar note, in the Hunt - Summerscale game white can improve by playing 19.Qc1-e3, again stabilising the center and depriving black of the counterplay he requires to justify his sacrifice.

Finally, if the above fails to convince, white can also venture 15.g3 (instead of 15.Ne2) which seems to lead to a slightly better ending for white (see, for example Ledger - Pert 1999).