How many times have you read the caution that an advantageous chess position "won't win itself"? The same holds for a disadvantagous position - say, one that White has at the beginning of the Jerome Gambit. White's game "won't lose itself", either; Black has to make it so. In the following game, the defender slips into carelessness, becoming inefficient - and his game suffers.
Wall, Bill - NN
Florida, 2019
1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+
4...Kxf7 5.Nxe5+ Nxe5 6.d4 Bb6
Black's move maintains his advantage. It is not as complicated as 6...Qh4, nor as simple as 6...Bxd4. There are 153 games with 6...Bb6 in The Database; interestingly enough, White scores 57%.
More importantly, Bill is 19-0 against the move.
7.dxe5 Ne7 8.Qf3+ Kg8
Bill has also faced 8...Ke8 9.O-O (9.Qg3 Ng6 10.Bg5 Ne7 11.Nc3 h6 12.Bd2 Rf8 13.O-O-O Rf7 14.e6 Rf6 15.Qxg7 Rxf2 16.Bxh6 d6 17.Qh8+ Black resigned, Wall,B - Guest2896104, PlayChess.com, 2019) 9...Rf8 10.Qh5+ g6 11.Qxh7 d6 (11...g5 12.Qh5+ Rf7 13.Bxg5 c6 14.Nd2 Qc7 15.Nc4 a5 16.Nd6+ Black resigned, Wall,B - WGMS, FICS, 2017) 12.Bh6 Rg8 13.Bg5 Be6 14.Nc3 Qd7 15.exd6 cxd6 16.Rfd1 Kd8 17.e5 Bc5 18.exd6 Bxd6 19.Ne4 Kc8 20.Rxd6 Qe8 21.Rxe6 Black resigned, Wall,B - Guest11863268, PlayChess.com, 2018.
9.Qb3+ Kf8 10.O-O Ng6
This is an improvement over 10...d5 seen in Wall,B - Guest6791785, PlayChess.com, 2018 (1-0, 17).
11.Qf3+ Ke8
The better retreat. Black should not be hypnotized by the g8 square, as he is better in the game: 11...Kg8 12.Qb3+ Kf8 13.Qf3+ Kg8 will only draw.
12.Nc3 d6
Or 12...Rf8 as in Wall,B - Guest5463336, PlayChess.com, 2018 (1-0, 15).
13.Nd5 Nxe5 14.Qg3 Ng6
15.Bg5 Qd7 16.a4
White can afford to be patient: from a practical point of view, Black is hampered by his Queen blocking in his Bishop, which, in turn, restrains his Rook - a classic Jerome Gamit defender illness.
16...Rf8 17.a5 Bc5
You've got nothing, Black likely thinks, and, as a result, he becomes careless and inefficient. The Bishop needed to go to d4, and then f6, directly.
18.b4 Bd4 19.Rad1 Be5
Giving away another free tempo.
20.f4 Bf6 21.Bxf6 gxf6
22.Qc3
Double attacks on both c7 and f6.
My guess is that Bill passed on 22.e5 because after 22...fxe5 23.fxe5 dxe5 24.Nf6+ Black can take the annoying Knight with 24...Rxf6, when 25.Rxd7 Rxf1+ 26.Kxf1 Bxd7 would give Black a Bishop, a Knight and a Rook for his Queen. The position might well be "dynamically equal", but there was no need to find out, when the text was available.
22...c6
The King had to go to d8 to protect the c-pawn.
23.Nxf6+ Rxf6 24.Qxf6 Qe7 25.Rxd6 Qxf6 26.Rxf6 Ke7 27.e5 Bd7
White has a Rook and 3 pawns for a couple of pieces. Those dangerous "Jerome pawns" give him the advantage.
28.Rd1 Be6
A slip tht hastens the end.
29.f5 Nxe5 30.Rxe6+ Black resigned
Gambits are all about development and attack. Failing to defend against gambits is often about lack of development, and its consequences. Witness the following game.
Wall, Bill - WGMS
FICS, 2017
1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+
4...Kxf7 5.Nxe5+ Nxe5 6.d4 Bb6
Again, a reasonable line. See "A Reasonable Line".
7.dxe5 Ne7
Not the only line Bill has faced, to wit -
7...Qh4 8.Qf3+ Ke7 (8...Ke8 9.Nc3 Ne7 (9...Bxf2+ 10.Qxf2 Qxf2+ 11.Kxf2 Nh6 12.Nd5 Ng4+ 13.Kg3 Kd8 14.Bg5+ Nf6 15.exf6 h6 16.fxg7+ Ke8 17.gxh8=Q+ Kf7 18.Rhf1+ Kg6 19.Qxh6 checkmate, Wall,B - Shillam, lichess.org, 2016) 10.g3 Qh3 11.Be3 d6 12.Bxb6 cxb6 13.exd6 Ng6 14.Nd5 Qd7 15.Nc7+ Kd8 16.Nxa8 Qxd6 17.Rd1 Ne5 18.Rxd6+ Ke7 19.Qc3 Kxd6 20.Qd4+ Ke6 21.Nc7+ Kf7 22.Qxe5 Rd8 23.Nb5 Bg4 24.Qf4+ Kg8 25.Qxg4 a6 26.Qe6+ Kh8 27.Nd6 Rb8 28.Nf7+ Kg8 29.Nh6+ Kh8 30.Qg8+ Rxg8 31.Nf7 checkmate, Wall,B - Itboss, lichess.org, 2016) 9.Nc3 Nh6 10.Nd5+ Kd8 11.O-O Bd4 12.g3 Qh3 13.Bg5+ Ke8 14.Nxc7 checkmate, Wall,B-Guest6766281, PlayChess.com, 2017;
7...d6 8.O-O Be6 9.Qf3+ Ke8 10.Nc3 a6 11.Be3 dxe5 12.Qh5+ Bf7 13.Qxe5+ Qe7 14.Qxg7 Qf6 15.Bh6 Bd4 16.e5 Qg6 17.Qf8+ Kd7 18.Qxa8 Qxh6 19.Rfd1 c5 20.Qxb7+ Ke8 21.Qb8+ Ke7 22.Ne2 Bh5 23.Nxd4 Bxd1 24.Nf5+ Black resigned, Wall,B - TenAndOnly10, lichess.org, 2016; and
7...Qe7 8.Qf3+ Ke8 9.Nc3 Qxe5 10.O-O Nf6 11.Bf4 Qh5 12.Qg3 d6 13.Qxg7 Rf8 14.Nd5 Qf7 15.Bh6 Nxd5 16.Qxf8+ Qxf8 17.Bxf8 Kxf8 18.exd5 Bf5 19.c3 Re8 20.Rfe1 Be4 21.Rad1 Kf7 22.Kf1 Re5 23.f3 Bg6 24.Rxe5 dxe5 25.Ke2 e4 26.b4 exf3+ 27.Kxf3 Bh5+ 28.g4 Bg6 29.c4 a6 30.d6 cxd6 31.Rxd6 Bb1 32.Rxb6 Bxa2 33.Rxb7+ Ke6 34.Rb6+ Kd7 35.c5 Black resigned, Wall,B - NN, lichess.org, 2016.
8.Qf3+ Ke8 9.O-O Rf8 10.Qh5+ g6 11.Qxh7 g5 12.Qh5+ Rf7 13.Bxg5
Despite Black's dogged Kingside defense, it is likely that White's four pawns are worth more than Black's extra piece.
13...c6 14.Nd2 Qc7
Getting out of the pin on the Knight, but Black needed the freedom that would come with 14...d5.
15.Nc4
Targeting the d6 square, which Black overlooks.
15...a5 16.Nd6+ Black resigned
Black can avoid mate only by giving up his Queen.
