Chess is a thinking game. Thought processes and time management are intertwined and are two of the most important skills.
I break down time management into two sub-skills:
- Macro Time Management: The ability to use almost all of your time every game without getting into unnecessary time trouble.
- Micro Time Management: The ability to allocate more time to the moves which require more thought.
Micro Time Management can broken down further into two parts:
- The clock situation, which includes how much time you have remaining on your clock, and, if there is a non-sudden death time control (e.g. 40 moves in 90 minutes), the current move number (and thus how many moves are left in the time control).
- The position on the board with respect to how much time the current move deserves. This latter aspect of Micro Time Management can be called the Criticality Assessment.
Usually a critical position calls for extra care and extra time. What can be considered a critical position? Let's start with a list provided by GM Lev Alburt and Al Lawrence in their book "Chess Rules of Thumb."
Rule of Thumb #135 is
"Recognize five characteristics of a critical position:
- When the game changes from known theory into unknown territory, from opening to middlegame, or from middlegame to endgame.
- When any pieces are exchanged, especially queens.
- When there is any change, or possible change in the pawn structure—especially in the center.
- When you have a tactical (short-lived) advantage which will disappear if not exploited now.
- When you see a move which seems to win."
Their very next Rule of Thumb, #136, is:
"A critical position is one about which you should think long and hard."
This is all good stuff, and I would like to add more on the subject.
A critical position is one where if the best move(s) are not chosen, then the likely outcome of the game is affected.