Large tournament fields require the following, which are in no particular order 1) Skill, 2) Lots of Luck, 3) Endurance 4) Patience 5) Timed Aggression

When you were sitting on 80k, that was a healthy stack, and when you got tired, you made some ill advised decisions with the pots that you were committed to. It happens.

My only advice would be, try to avoid those tournaments that are going to run into the nether hours of the night/early morning, unless you're going to have the ability to still have all of your wits about you in the late stages. It is then that all of the decisions become increasingly important. In the hand that took you to 680, your opponent only had two pair. Not exactly the strongest of hands.

I've made plenty of mistakes in the wee hours of the morning, but I've also been able to take advantage of some players that were effected by the early AM play as well.

Large tournament fields require the following, which are in no particular order 1) Skill, 2) Lots of Luck, 3) Endurance 4) Patience 5) Timed Aggression

When you were sitting on 80k, that was a healthy stack, and when you got tired, you made some ill advised decisions with the pots that you were committed to. It happens.

My only advice would be, try to avoid those tournaments that are going to run into the nether hours of the night/early morning, unless you're going to have the ability to still have all of your wits about you in the late stages. It is then that all of the decisions become increasingly important. In the hand that took you to 680, your opponent only had two pair. Not exactly the strongest of hands.

I've made plenty of mistakes in the wee hours of the morning, but I've also been able to take advantage of some players that were effected by the early AM play as well.