What are the ideas of 6. Qf3 in the Scotch?

Question

In the following sequence of moves, what are the main ideas of the fashionable 6. Qf3 in the Scotch? Can White hope for a real advantage by letting Black trade Queens so early and worsening (at least from a theoretical point of view) his Pawn structure?

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1. e4 e5 2. Nf3 Nc6 3. d4 exd4 4. Nxd4 Bc5 5. Nxc6 Qf6 6. Qf3 

PS: Another strange-looking early Qf3 by White that has become popular recently! Others are in the Sicilian Taimanov and in the Exchange Alekhine...

Answer 1

I only see three alternative moves to defend the f2 square: 6.Be3 Bxe3 7.fxe3 results in doubled isolated center pawns, not something I would like to play with. 6.Qd2 and 6.Qe2 block the bishops.

I guess it's a matter of what you like to play with. If you block one of your bishops, you can later play the queen again or fianchetto the bishop. 6.Qd2 and then fianchettoing your dark-squared bishop requires more moves as the black queen controls the b2 square. 6.Qe2 blocks in your light-squared bishop taking you longer to castle (short).

After 6.Qf3 Qxf3 7.gxf3 you can still castle long and you have quite a strong centrum pawn formation. Perhaps this looks better than the alternatives.

Answer 2

After 6.Qf3, black can

1. Not initiate Q trade 6... gxc6 7. Be2 or Nd2. In this case black's N has some develop problem as Q is blocking its natural f6 square.
2. Trade Qs 6... Qxf3 7. gxf3 bxc6 8 Be3. And normally after that 8... Bxe3 fxe3. In this case, white has better central control. White's K normally stays behind and guards the e/f pawns. Black's weak a pawn can be more problematic than white's h pawn since white's rook has more room to lift and roll over.

Of course all these are theoretical and even if they are in white's favor, it's very small.

One variation that's good for white is if black tries to keep pawn formation by taking dxc6. In this case white has a winning king and pawn ending so he can just try and trade everything, starting immediately by trading Qs and dark Bs.

Answer 3

I don't think white minds gxf3. He gets a half-open g file for his rook and he is capturing towards the center. I suppose black will respond with bxc6 and I would play Nd2 going for Nb3 next move and asking black where his bishop will go. If it goes back to b6 then pawn a4 seems like a very nice position for white, while other moves he will play f4 anyways and establish a slightly better position from what I can see.