<1.Qxd8†?> is definitely worse after <1....Kxd8 2.Rxh8 Rxa1> which removes the Rook threats <3.Rxg8 Ke8!> and with one Rook these piece-up positions are usually drawn! If White wants to safe one of his pieces he loses some his initiative, i.e with <4.Bd3 >, yes, only according to Rybka with 0.5 for White. After all, how is White going to win the R+N vs R endgame? He isn't. Same for the best starting move:

<1.Bb5†> seems the best move. <1....Nd7> is the ONLY defense, in either other defense besides Bd7 the Black Queen falls (showing the strong White initiative) and after Bd7 White can continue with 2.Rxa8! Rxh1?! 3.Bxd7†! and Black loses: either 3....Nxd7 4.Rxd8† or 3....Qxd7 4.Rxb8† and White has check in a deadly position.

<2.Qe2† Qe7> again any other move loses: try it out, Kf7 leads to mate, and N/Be7 lead to Rxh8 . Take note that White holds initiative.

<3.Rxa8 Qxe2†!!> instead of the symmetrical Rxh1?? suggested: than, the White win is very trivial being up a piece where it matters (Queens OTB!) and up in position. After Qxe2, it's not a clear win without the Queens!.

<4.Kxe2 Rxh1 5.Rxc8 Kf7! > and White's extra piece should not decide the game, as there are no pawns. But this IS Black's only drawing option, and the endgame at hand is not very easy.

Rybka shows a steady 0.58 through the entire variation, referring, probably to the drawn R+B vs R or R+N vs R endgames. The position ensued in the 'main' variation is a good one for White, but the win does not seem to be there:

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"But I don't know how to play."

"Oh, that's what everyone says. Come on, be a sport." So they sat down, and here is what happened:

<1.e4 e5 2.d4 d5>

"That's unusual", thought White. Now, of course he might have tried 3.exd5 exd4 4.Qxd4, but he knew all about hustlers who protested they didn't know how to play just before announcing mate in 10. So, fearing a trap:

<3.dxe5 dxe4>

"OK, let's end this foolishness right now!"

<4.Qxd8+ Kxe1!!>

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Now Capa plays a move that he would not normally even look at. 9. Qd2 allows black to play 9....Nxf3+ and Fritzie says that the game has swung from a small white advantage to a small black advantage.

White wins handily because black doesn't take his chance to vary the symmetry and allows a forced mate.

So why 9. Qd2? I guess that Capa looked across the board at this cheeky NN and decided to teach him a lesson. So he played a move that was objectively not the best, but which allowed a quick finish if black continued to copy. And black obliged.

If black had had his wits about him, this was the point to vary. In that alternate universe we would have been questioning Capa's relatively weak 9. Qd2 rather than praising his subsequent play. I have no doubt that Capa would still have won, but it would be more difficult for him.

Reminds me of the oft repeared story where Capa offers to play a stranger at queen odds. The stranger protests, saying that Capa does not know him and so cannot know whether he needs queen odds. To which Capa famously replies: "Sir, if you could beat me, I would know you."

9...Nxf3+ 10. gxf3 Bxf3 11. Bxf6 gxf6 12. Qh6 doesn't look right, so maybe 9...Nxf3+ 10. gxf3 Be6 11. Nxf6+ gxf6 12. Bh6.

Now if 12...Bh3 13. Bxf8 Bxf1 14. Bxd6 Bxd3 15. Bxc7, White successfully exploits the asymmetry and wins a pawn. But if 12...Re8 13. f4 and I don't see the <small Black advantage>.

Here's your first line:

<9...Nxf3+ 10. gxf3 Bxf3 11. Bxf6 gxf6 12. Qh6> and now black should play 12....Kh8

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With Rg8+ threatened, white is in a world of hurt. White will have to throw a lot of material to prevent mate. Probably lost for white already.

Instead, Fritz prefers a quieter line:

9... Nxf3+ 10. gxf3 Bxf3 11. h3 c6 12. Nxf6+ gxf6 13. Be3

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