I agree in principle, but you have to take into consideration the fact that most of the risk in these decisions lies with the employee. Misjudge, and it will be

I agree in principle, but you have to take into consideration the fact that most of the risk in these decisions lies with the employee. Misjudge, and it will be a very unpleasant few months. As a rule of thumb, I would avoid giving more than required notice when quitting because you're unhappy with the job. There's no way to explain it that won't eventually create a poisonous atmosphere. If it's something less emotionally loaded, like moving to accompany a spouse or to go back to school, then a couple of months notice could be seen as a noble gesture. Any longer and there's no realistic benefit for the employer, but plenty of risk for the employee.