This line is also known as the Kopec Defence, distinguishing it from e.g. 2...Nc6 or 2...e6, say.

Don't let this one game discourage you from what seems to be an admirable policy.

Playing a player that much higher rated than yourself -- 800 points rating differential -- you have to adjust your expectations. If you don't make any horrific blunders and force them to win the game rather than giving it away, it was a success even if you ultimately lose. And being aggressive is never a bad thing, ESPECIALLY playing White against the Sicilian. Always play with fire and spirit.

Although I play in a different order (e5-d5-Nf3-Nxd4-Nc3), this is a position I find myself in a lot. It definitely looks a good position, but then it is still about even on the database.

This is where you get a branching of the ways, Black having such a wide choice how to proceed. White has an easy development for which he has given up a centre pawn for a flank one.

My aim was to move you towards the Sozin Variation. www.supreme-chess.com

I play 6. Bg5 here, because I'm looking to castle on the queen-side and push the king-side pawns. I suppose it is all down to preference though.

Both are aggressive lines. The line played here used to be a favorite of Boby Fischer. The idea is to induce Black's e-pawn to advance one square, then at some point bring forward the f-pawn to strike at the target thus created.

It isn't so bad. 7. Be3 may be a slightly better alternative in the current position, given that you're preparing for O-O.

Thematic, but maybe it doesn't go so well with the B on c4. But that is something worth testing. If such a fine looking developing move is wrong, here, then it's up to Black to 'prove' it.

Nothing wrong with your move, it's a natural development move.

According to GM Bruce Pandolfini [in one of his annotations to the second Kasparov-Deep Blue match in which a computer seized the title of World Champion, which humans have thus far not reclaimed] "The two pieces really are about equal. It's just that the handling of Knights requires more ingenuity."

The value of the N vs Bishop all depends on the position, but more often than not, the bishop is slightly better. The greater the imbalance of pawns, the better the bishop.

I agree mostly with dmaestro. My preference changes depending on the game position

This is also why I think White should castle on the long side. If he castles on the king-side, he is inviting pressure from Rg8.

One of Black's threats was ...Nxe4, hence the exchange.

It does seem to be the only way to retain material equality - however I'm not sure a bishop and knight are as effective as two bishops.

The effectiveness of any pair of minor pieces depends on what else is going on on the chessboard. But if the bishop pair become more mobile than the B/N pair, then they must be preferred.

Being too hard on yourself here, I would have been happy with either White or Black here

Observe that Black is quite untroubled at leaving his flank pawns both isolated. That central pawn majority could well become a major factor in the game.

This opens up dark square weaknesses and eventually ...d4 will likely drive the B anyway.

You've made a fianchetto on g7 very attractive

Mind you, those open b- and g-files might well become assets for Black into the bargain.

As Ion says, I was looking at the open g-file. If you copy the board down onto a piece of paper and highlight all of the squares that your major pieces can directly affect, what do you notice?

Up until now White has played quite well. I would recommend 12 N-K2 if you fell you must move the Knight here.

I was expecting either Qd3 or h3, to try and mitigate the threat of my open g-file. Na4 however, is not anywhere near as bad as you seem to think. It's more of a delaying move, forcing me to protect my Queen rather than continue my attack

Still concentrating too much on your queenside. I expected f4.

I would have been very reluctant to move this pawn... Had White allowed the pawn to continue to h3, he could have taken or just advanced his own g-pawn one square. True, this would have weakened his light squares, but he retains his LSB, which would have been a help.

This is a weak move.

As Ion says, not a great move. I was expecting pawn to f4 again, resulting in a weakening of your light squares after 14...h3 15.g3

Rd8 a subtle move. The plan Rg8, Qg4 seemed a lot more straightforward, but kind of naive too. Black is happy with your knight to be in such a weird poisition, its only function being to prevent the black queen to go to the black diagonal. Your queen move looks ok, but observe your king is defended only by the queen... a major piece, than cannot be exchanged. Your emergency plan should be Kh2 - Rg1 or something like that...

Unfortunately, Black has built up a mini-fortress in the middle and looks set. He has no intentions of castling now. Things are starting to look perilous for White. The exchange is better than the move you played, as you said, but I wonder if 16. Be2 might be your best move. It'll force Black to exchange or move his queen, and you get to keep some protection on the king-side.

I think White needed to decide right now whether he wanted Queens on or not, and acted on that decision. There's much to be said for keeping queens on, as offering more variety in defence, but exchanging on h5 was a reasonable option. By prevaricating, White allows an exchange that is rather more favorable to Black, weakening his pown pawn structure, and leaving the h-pawn 'en prise'. Up to here, White had been maintaining a rough balance. Now the scales tip sharply in against him. Black's infantry centre is not to be sneezed at, neither.

I would personally choose to play 16 QxQ here simply to reduce Black's attacking chances. When one is on the defensive, exchanging off the attacking pieces can buy one time to strengthen one's defense plus it reduces the amouint of force your opponent can throw at you.

I like Be2, if Black takes, the bishop can defend g2

Ion has the most insightful comment again, you needed to make a decision. By not either retreating or exchanging, you allowed me to destroy your defence, cracking a big hole in the centre of your pawn structure. I can't say which would be better, but I would've exchanged in your position

Maybe 18. Kh1 with an intention to play 19. Rg1 and provide some support on that g-file?

Surprisingly, Black lets the h-pawn live! I was expecting 17...Bxh3 18.Rfe1 Rg8ch 19.Kh2 Bg2 with threats like ...Bxf3 and ...Bh6 ready to go.

I think the idea is, how does W really defend the h pawn? If now Kh2, Bf4+. If Kg2, Rg8+. Black is focused on getting to the K.