Plot no Jutsu in fact exists. I agree it doesn't happen as often as people claim, but there were situations in which some characters survived situations of certain death without proper explanation or pulled a convenient new technique out of nowhere that is exactly what they needed to escape and/or accomplish X.
One of the most infamous examples was the way Sasuke avoided being pulverized by Deidara's final blast. He was already stated to be nearly out of chakra, but he somehow managed to summon the most colossal snake of the world to protect himself with no problems, placed a Genjutsu on it and entered its mouth to protect himself, and he did all of that in the lightspeed because the explosion was already off.
Another recent example was how Onoki wasn't killed when he tried to stop Madara's meteor. He flies into it and decreases its weight to zero avoiding a full-force impact, nothing wrong with that. But then Madara summons a second meteor that lands on the first one in full force while Onoki was still under it and he survives. Let it sink for a while, he was directly beneath it and survived a meteor wedge on his face, he should have been crushed like a bug, but he survives with just a wound on his forehead. Remember up to this point he was always portrayed as a frail old man with a back problem.
I just cited two examples, there's more, but I think it is enough to prove my point. While some people have the annoying habit of pressing the PnJ button for trivial things and usually in situations it doesn't really apply, Kishimoto made actual uses of plot armor before. Is it bad writing? Yes, but just for a brief moment, even geniuses screw up sometimes, write themselves into corners and have to appeal. Kishimoto is not an exception, unless of course you want to view his work as completely flawless, which is just the opposite, but equally annoying, polar extreme of the hater.
