Good endgame technique can usually compensate for weaker play in the previous phases; in practice, an impressive number of half and full points can be saved by superior play in this last part of the game. Mihail Marin, Secrets Of Chess Defence
When measuring compensation for an exchange, it is always a good idea to check out the mobility and effectiveness of the rooks of the side that enjoys an 'extra' one. Peter Wells, Winning With The Trompowsky
The great thing about an opening like the King's Indian Attack as White is that it is more about piece-placement and positional motifs that it is about specific book lines. Steve Stoyko, Lecture - Kenilworth Chess Club
The Open Variation (of the Ruy Lopez) has a large number of variations to choose from. Both sides have options on so many moves that very little has been definitively worked out. This is an ideal system for the average player, both from a practical and educational point of view. John Watson, Mastering The Chess Openings - Volume 1