It really depends on the product your making, the size of your company and it's corporate culture.
Essentially "Keeping your staff" would seem work best in a situation where you a moderately popular developer who doesn't have huge brand recognition... and is clear in it's culture.
You have to be moderately popular, because well... you need money to pay developers. Paying development teams is expensive. Having them sit around is troubling and you don't want to run into a bad project.
You shouldn't have huge brand recognition, because if your Call of Duty, who cares... the main value is in the brand. Though if your call of duty you may do this simply because your always making the next Call of Duty.
You have to be "clear" in your culture, because otherwise you might just end up making the same unpopular games time and time again. Fresh workers can shake things up in a stagnant culture that is out of touch.
