Not quite. It is statistically more reliable in such conditions in a sense that it will have a higher mean rounds to failure number compared to most everything else. But MRTF won't be infinite. In fact, it'll still be low enough that you will definitely notice.

Then there's the reason why. Loose fitting and massive parts, yes - but that also requires overgassing to move those massive parts (and then it also moves them faster than they actually need to be moving to cycle). So you're basically sacrificing energy efficiency for the sake of some extra oomph to clear problem. On any cycle that doesn't actually have a problem to clear, the sacrificed energy is wasted.

Then there's the normal metal stress and fatigue when running something 24/7 non-stop. Here's what happens when you do it to an AK - the guy is running a full auto rental range in Vegas for tourists, and shared his experiences about how soon guns fail, their failure modes etc: http://www.ar15.com/forums/t_4_64/159106_AK_abuse__update_on...