The task of defeating the Jerome Gambit (1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+) can be turned into a simple rule: exchange down to the endgame and make your extra piece count*. Of course, the asterisk (*) is there to remind defenders that they shouldn't let anything bad happen to their King while they are following the rule...
blackburne - Crusader Rabbit
JGTourney4 ChessWorld, 2009
1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+
4...Kxf7 5.Nxe5+ Nxe5 6.Qh5+ Ke6
A tough defense for White to handle, if Black knows what he's doing. Fortunately for the Jerome Gambit Gemeinde, that doesn't always happen.
7.Qf5+ Kd6 8.0-0 Ne7 TN
Many excursions away from "book" are not improvements; but this move is just fine. Hats off to Crusader Rabbit.
9.Qf4 N7g6 10.Qg3 Qe7
This is solid, but better was either breaking the pin with 10...Ke6 or offering to exchange Queens with 10...Qh4. White's response is thematic.
11.d4 Bxd4 12.Rd1 Kc5
Black will have to return a piece, but it looks like the only thing he has to be worried about is his wandering monarch.
Looks can be deceiving: the next time this position appears, White should look at the shot 13.Rxd4, as after 13...Kc6 (13...Kxd4? 14.Qe3+ Kc4 15.Qb3+ Kc5 16.Be3+ Kc6 17.Qd5 checkmate) 14.f4 the game is even.
Gotta love that Jerome Gambit!
13.c3 Bxf2+ 14.Qxf2+ Kc6
Despite his exposed King, Black is doing fine. It is White's job to make as much mischief as possible.
15.Qd4 b5
Either too casual or too panicky. The routine 15...Qc5 was what the position (and the King) needed. Now things get dangerous for Black.
16.Qd5+ Kb6 17.Be3+
17...Ka6
Another reflection of the psychological stress of defending (against the Jerome Gambit, of all things): Black's inconsistency is his undoing. He should have continued with 17...c5, when White's followup will produce a complicated game that still favors the second player: 18.b4 d6 19.Qxa8 Bb7 20.Rxd6+ Kc7 21.Qxa7 Qxd6.
White is now winning.
18.a4 c5
The addition of White's Rook to his attack is devastating. Black's "best" was 18...c6 when White's play unfolds with intensity: 19.axb5+ Kb7 20.bxc6+ Kc7 21.Bc5 dxc6 22.Bd6+ Kd7 23.Qc5 Qe6 24.Bxe5+ Ke8 25.Bxg7
19.axb5+ Kxb5 20.Qxa8 Nc6 21.Na3+
White's Queen is safer than Black's King.
21...Kb6 22.Nc4+ Kc7 23.Rxa7+ Nxa7 24.Qxa7+ Kd8
25.Bxc5 d6 26.Bb6+ Ke8 27.Nxd6+
All of White's pieces join in. Compare that with Black's Rook in the corner.
27...Kf8 28.Nxc8
28.Qa8 leads to mate; but the text wins easily as well.
28...Qe6
Allowing mate.
29.Rd8+ Qe8 30.Rxe8+ Kxe8 31.Nd6+ Kf8 32.Qf7 checkmate