Time Controls: Why too little or too much time hurts my game (and probably yours)
I truly believe that there is an ideal time control range. I recently read Malcolm Gladwell's David and Goliath about how apparent advantages can really be disadvantages and vice-versa and I feel this applies to chess time controls. For example, in the book he talks about class size in the school system. Most think that the smaller the class, the better, but he actually shows that if a class is too small it can hurt the educational process as much as a class that's too big. This is just one example of many he cites, and this concept (of an ideal size of something - not too big or too small) can be represented visually by the "inverted U-curve").
This is true for time controls in my view, at least for those of us non-titled players. As far as non-blitz (regular rated) games, I know if I play those horrible (in my view) dual-rated time controls (G/30 through G/60 inclusive of time delay), the quality of my play goes down, yet if I play the REALLY slow time controls such as 40/120, SD/60, my play suffers as well! In the former, I have to move quickly and I'm more blunder prone. In the latter, it's actually too much time! My mind starts to lose focus, much more mental endurance is required, and it gets to a point where more thinking on a particular move is counterproductive. On paper, one would think that more time equals better play, but in actual practice I don't find that to be the case.
I feel that the best time controls are in the G/90 to G/120 range with a 5 second delay. That range is slow enough that I can think without feeling rushed, and yet fast enough that my brain won't be fried by the time the late middlegame or endgame approaches. It's the perfect balance from my perspective. If you feel differently, please chime in below...