I really like to play openings that contain f4 (f5 as black) for a number of reasons.
- It cannot be challenged with d pawn, which is initially protected by the queen.
- When the king knight is developed, the f pawn is no longer blocked.
- Unlike c pawn, it can be easily supported by castling kingside up to the board, and helps the development of the rook if exchanged.
- After king's pishop fianchetto, the diagonal is open and the bishop is very strong there.
- Even if exchanged early, after castling kingside, the king rook has a semi-open file, which makes it stronger.
- Enables Ng5 move, which can be nasty sometimes.
But usually this move is considered bad, or dubious at the best by grandmasters and engines. What is the reason?
[FEN ""] [StartPly "3"] 1. e4 e5 2. d4 exd4 3. f4 Nc6 4. Nf3 Bc5 5. Bd3 Nf6 6. e5 Nd5 7. O-O O-O 8. Kh1
[FEN ""] [StartPly "3"] 1. e4 e5 2. d4 d6 3. f4 exf4 4. Bxf4 Nf6 5. Nc3 Nc6 6. Nf3 Bg4 7. Be2