When playing versus the isolated pawn, try to exchange minor pieces - particularly knights - and retain at least one pair of rooks. Alexander Baburin, Winning Pawn Structures
Practice shows that, for the sake of creating a connected pair of pawns at d5 and e5, a sacrifice of material is often fully justified. Alexey Suetin, Plan Like A Grandmaster
Almost all combinations are made possible by an undefended or inadequately guarded piece. This means that whenever you see a piece that is "loose," perk up and look for a trick to take advantage of it. Jeremy Silman, The Reassess Your Chess Workbook
Too often amateurs get the impression that grandmasters are calculating wizards who constantly think 10 and 15 moves ahead. Actually, there are few times in a game when you have to look more than four moves ahead. Andrew Soltis, Confessions Of A Chess Grandmaster
As a general principle, open games - those starting with 1.e4 - are best for attacking players. This is because mobilisation of the pieces most suited for attacking Black's king (the queen, king's bishop and king's knight) occurs much more rapidly after 1.e4. Edmar Mednis, Practical Opening Tips
Thou shalt not trade down to a king-and-pawn ending unless you can safely bet your first-born child on the result. Andrew Soltis, Grandmaster Secrets - Endings
If master players do not castle early, there is usually a good reason. When lesser players don't castle, they are usually misjudging the position. Andrew Martin, ChessMoves magazine