I know how many disadvantages there are to sitting out, and I know if you REALLY want to finish far, the better path is patience and playing the whole way through(I have plenty of patience and do this all the time) but there IS something to sitting out DEPENDING on your situation. It really depends on your goals. You need to do the math to sit out for a good period of time in the right tourney. I always do the math, and I know when it can be very advantageous to lose the least amount of money possible. If you are just trying to finish in the money, which is what I always do, then sitting out CAN HELP get you there! If you're trying to get a really high placement, then DON'T. The thing about sitting out is, you prevent yourself from making mistakes or from being harmed by bad beats. It all depends on what kind of chances you want to take and where you want to be. Example: You can take a 50% chance to finish barely in the money or a 5% chance to finish first or not in the money at all. This might not be a realistic example, but it's just to show what you want your GOALS to be. It's different for everyone, and I'm just saying sitting out is an option depending upon your situation(and if you do the math for the tourney.)
I know some people will NEVER sit out, and that's perfectly fine. The point I'm trying to make is that it IS a valid tactic, if you want to use it.
It's all dependent on the person.