Two Knights' Defense 4.Ng5 Nxe4

This is one of the trickier lines in the 4.Ng5 variation.

The choice of 4...Nxe4 is probably as good or better than the Wilkes Barre where Black sacrifices the f-pawn for an attack. The correct response is indeed, 5.Bxf7ch Ke7 6.d4 h6 7.Nxe4 Kxf7; White is at a crossroads. He can stay a pawn up with 8.dxe5 d5 9.exd6 e.p. or push with 8.d5. Which is better? If White was assured of getting a strong attack with 8.d5, then that would make sense, but it seems that Black, with accurate play can safeguard his King and keep the minor exchange. In an open position such as this, long term that is a problem for White i.e. what happens if Black consolidates and begins to make trouble for the Knights?

For this reason, I prefer 9.exd6 e.p. because then Black has to make up the 1/2 pawn deficit i.e. he is down a pawn for the minor exchange. While Black can threaten the b-pawn, it is better for White to just try to consoiidate, get good squares for his pieces and then make the extra pawn count. While the initial thread shows a way for White to win quickly, it is unforced, thus players should be cautioned that the player of the Black pieces has reasonable prospects of equalizing if White plays second best moves (not even blunders).

Probab;y White should play 4.Ng5 Nxe4 5.Bxf7ch Ke7 6.d4 h6 7.Nxe4 Kxf7 8.dxe5 d5 9.exd6 e.p. Bxd6 10.Nbc3! +/=

It's cool that you bring up this line.

Several years ago I played a game against my father where he played that line against me and at the time I thought he invented it. As it turned out after doing some research, it was played over 100 years ago and also mentioned by Staunton. But I still found it pretty interesting and began using it too. White players rarely react correctly when facing it for the first time, and I've often (in blitz anyway) faced Nxf7 which loses by force.

I talked to a GM about it and he said White is also better after d3 instead of the supposed refutation of the entire line with d4. However that line does get pretty complicated and I'm not sure if he had a specific line in mind. As we can see in the Harding article it turns out well for Black.

So overall I think it's a good practical choice for us club players, and it's a pleasant sign when even a GM who's usually well prepared would rather play 6.d3 instead of the "refutation" to avoid falling into a well prepared line.