What is stopping me from running through a rift, say, with my best gear, and then, right before I am about to kill an elite, quickly shifting to my magic find gear, killing the elite, and then switching right back to my best gear? Is Diablo 3 smart enough to realize that you are 'gaming the system', so to speak? I feel as if they don't nerf your MF when you do this, then the minimal time it takes to switch back and forth will not offset the increased legendary drop rate (as doing an entire rift with your MF gear might).
Certainly people have thought of this before. Is it really that easy, or is there something in place to prevent this?