Personally, I play best when I just sit at the table. I will defend my starting point aggressively, but am not over aggressive. I am not pressed by a short stack, or enter extra hands to try and steal a win because I have a cushion. I play my best game until I reach my desired % of earnings at the table. I don't have a hard fast rule that I will walk away from the table once I exceed those earnings, but if it is an extended session where I have been unable to get much traction at the table over an extended period of time I will sell out of my position and take my earnings to a new table to reestablish better position.