5.d4!
what's the idea behind this move?
Something like that.
Notice that it's not only the f4 square, but in certain cases the d4 one, as well.
thanks!
Absolutely thanks
In the 5. d4 there's still some lines for black:
The engine evaluates the end position as equal.
In the 5. d4 there's still some lines for black:
The engine evaluates the end position as equal.
The right approach is still 7.Bxf7+ Ke7 8.Bc4 b5 (effectively the only good move) 9.Bd3 (or even 9.Be2) with advantage to white. This has been played many times.
THe engine evaluates +0.7, or about the evaluation of, say, the Modern Defence.
When you play well with your opponent doing their traxler you can destroy them. But if you play badly you will be destroyed even if your opponent plays badly near the end. So remember to play well 
When you play well with your opponent doing their traxler you can destroy them. But if you play badly you will be destroyed even if your opponent plays badly near the end. So remember to play well
That's not the traxler
The Traxler is garbage, but it should never happen as White then has played garbage to allow it.
1.e4 e5 2.Nf3 Nc6 3.Bc4 Nf6 and now 4.d3 or 4.d4 (matter of taste, one isn't better than the other) are FAR FAR FAR SUPERIOR to 4.Ng5?! (and I am being kind only putting a dubious symbol.
Black has 4...d5! 5.exd5 Na5! And equality is already reached in 5 moves!
As White, after 4...Bc5?, it is well known that 5.Nxf7 is an error. 5.Bxf7+! Followed by 6.Bd5! Is a clear advantage for White.
1.e4 e5 2.Nf3 Nc6 3.Bc4 Nf6 and now 4.d3 or 4.d4 (matter of taste, one isn't better than the other) are FAR FAR FAR SUPERIOR to 4.Ng5?!
No they aren't. All 3 moves are roughly equal, but 4.d4 leads to the least complicated positions out of the three, where black has easily equalized. Plenty of titled players use 4.Ng5 as their main opening.
The Traxler is not good mainly due to 5.d4.
5.Bxf7+ is also better for white, but leads to the complicated game black wants. 5.d4! is strongest and white is better with less risk.
5.Nxf7 is a draw by force.
The autors says that Kf1 is the best way to refute the traxler. Do you agree here at least.
Every chess engine recommends that white play 5.Nxf7 and after black plays 5...Bxf2+ white plays 6.Kf1 and, as things change, white may be able to play Kxf2 later on. There is a counterintuitive move that solves a lot of white's problems if he goes down this path:
1. e4 e5, 2.Nf3 Nc6, 3.Bc4 Nf6, 4.Ng5 Bc5, 5.Nxf7 Bxf7+, 6.Kf1 Qe7, 7.Nxh8 d5, 8.exd5 Nd4, 9.d6!