I am not one of those named, but maybe you won`t mind if I post ?
For a tournament player, I`d suggest that the area where it is critical to know something about the opponent`s behaviour is in the mid/late stages, where stack size is low relative to the blinds. This is a different game entirely from the early levels.
Therefore, when I make a note about the opponent`s deepstack play, I always differentiate it by marking it (d). A sound tournament player will change gears markedly as the tournament progresses. Don`t try to read his late game tendencies based on an early game read.
Most of my MTT notes are made in late game. Almost any hand that goes to showdown will provide information. Look especially at what range an opponent will shove from early/mid/late position when effective stack size is 15x BB or less.
Also, the range with which he will call such a shove.
Also, his stealing and restealing range (HEM or PT will provide a number for this, but beware if it is skewed by too many hands from early in the game, if the opponent has been at your table some time).
Finally, I always note if I have been at the final table with a player. If I meet him again in the late stages, I will then know that he is likely to be a solid regular. Additionally, I should probably assume that he is observant and will also recognise me.