Here is a variation which I could of reached in a Traxler game that I played last night and discussed with a friend. I figured it would be helpful to explore this further and write a post to document my thinking.
To reach this position, White had just played qf3 for defense purposes and threatening a black knight which was on e5. We discussed playing ng4 which we both felt was good. However Fritz pointed to the move played here by Black Nf6 which removes the target.
Here with WTM, his King and Queen are awkwardly placed. If he is greedy and takes the Rook out comes Nd4 an attack which gains a tempo. In the position above he can't move Ke2 due to the the Nd4+ royal fork.
The continuation of a game on chessgames.com with this line went
Although after the line 1. e4 e5 2. Nf3 Nc6 3. Bc4 Nf6 4. Ng5 Bc5 5. Nxf7 Bxf2+6. Kxf2 Nxe4+ 7. Ke3 Black played Qh4. A more popular line is 7....Qe7.
Here is a representative game from that line
and similar games to that