As a live NLH player, I often come to a find myself in a dispute of logic. Since the game is NHL and you could lose everything in one hand, the longer the session the greater the possibility of losing.

Thus, there has to be some magical time when you've played too long.

If you've been playing a long time, and winning, it may not be possible for you to lose it all in one hand, if you have the table covered. Anyway, the chance goes up that you can double up also, so aside from side effects of long sessions, there's no theoretical maximum session length.

In practice, your edge probably goes down sharply after some length of time, as you get tired, and obviously you shouldn't continue playing past the point where your edge get too small. This will vary from person to person.

Nothing magical there, I'm afraid.

You can just as easily lose you're stack at the start of a session as much as the end of one l,Although I do agree if you're feeling tired and not concentrating this could have an effect o how you play making more easy to lose you're stack

When the effective stack size becomes larger then what you are willing to play with according to your personal bankroll management rules?

Focus on the hand at hand, less on this type of stuff like losing your stack...

How about "I bought in, it is already lost, now it is my job to make the best of each opportunity, which sometimes might be leaving the table at the right time."

Questions to ask ourself but you'll know at the table when you no longer have any targets...that is when you leave. There is another game elsewhere for you then.

Brett

I don't understand you logic OP, if you view all your sessions as one long session theres no periodicity to when you loose a bi.

But when you sit at a table in a sharp, alert state of mind, you are much less likely to get stacked than 12 hours into the session when you are tired, hungry, grimy, and have very little focus or cognitive ability.

What about after several hours and the screen looks blurry and your mind is wandering?
I think this is what he's asking. When the "A" game ability is gone. Perhaps the process of evaluating when you've made too many mistakes and should call it a day?