- If you want your rooks to be effective, put them on an open file.
- Without open files, bishops or knights might easily outperform the rook, leaving it sitting passively behind its pawns.
- A half-open file is often used to exert tremendous pressure against weak enemy pawns.
- A file is very valuable because it's the road that the rook travels to infiltrate the enemy's position.
- Rooks are very powerful on the 7th or 8th rank.
- A rook on the 7th rank annoys the enemy king, but also targets all the enemy pawns that haven't moved yet.