Aggressive is the way when you are REALLY deepstacked, but if the blinds are huge you do have to be careful. I would tend to focus on stealing the blinds when in position (since you can steal with min raise you get v good
odds), but don't get involved in pots with marginal
hands. Ppl are in shoving mode in later stages, and even if you are a large stack, if you get too attached to a hand then you might find yourself losing 3/4 of your stack.
In the later stages, essentially everybody is short stacked, since even the chip leader probably only has 25xBB.
So steal blinds whenever you can, but don't try to steal blinds from really shortstacks with marginal hands since they will shove and don't play anything out of position unless you have a hand with which you might as well shove.
I tend to play late stage MTTs by folding alot, picking up blinds whenever i think i can (or im willing to call a shove by a short stack), and then waiting for a big hand. You can't be playing too aggressive unless you are a huge stack or every man and his dog is going to shove vs you and even losing 2 BB is huge at that stage of an MTT. So pick your spots, and don't get attached to a pot without a very good hand. But picking up the blinds is priority #1 in late tournament stages so you absolutely cannot ignore that.
But robwhufc summed it up the best...simple fact is it doesn't matter how well you play it you have to get a little (or lot) lucky to make a FT with >1000 ppl.