A noted economist once observed "If you never miss a flight, you are spending too much time sitting in airports." The theory goes like this: Suppose that by always leaving for the airport 2 hours before your flight, you would average sitting 1 1/2 hours in the airport, but you would never miss a flight. On the other hand, if you always left for the airport 1 1/2 hours before your flight, you would average 1 hour sitting in the airport, but you would miss 1 flight in 10 and you would have to wait 2 1/2 hours for the next flight. By choosing the first option you would be spending 5 extra hours waiting before flights in order to avoid a single 2 1/2 hour wait as the result of a missed flight. Ignoring the financial cost of missing your flight (which is exactly the kind of unrealistic assumption that noted economists are noted for making), the optimal time to leave for the airport is the one where you aren't spending any more extra time waiting before flights than the occasional missed flight would cost you,
Although it may not be possible to precisely determine the optimal time to leave, the noted economist's point is that if you never miss a flight, you can be pretty sure you haven't chosen it.
I tell the players I coach "If you never get in time trouble, you are probably moving too quickly." My logic is the same as the economist's. The more you think, the better moves you make and the more points you score. Therefore, unused time costs you points. On the other hand, time trouble also costs you points because you don't have adequate time to think and by using more time, you increase the risk of time trouble. Your optimal average thinking time per move would be the one where your average point cost for unused time is equal to your average point cost for time trouble. Move at a slower than optimal rate and points lost to time trouble outweigh points gained by thinking longer. Faster than optimal and vicey-versey. For a player who plays blitz well, the optimal average thinking time might result in time trouble once every three games while once in ten games might be the optimal for someone else.
Although there is no way to be sure that you have actually hit the optimal average thinking time, if you never find yourself in time trouble you can be pretty sure that you can get closer to optimal by increasing your thinking time.