Above reasons is why I run PuP on mine for situations like this:
http://replay.pokemonshowdown.com/ou-110111219 (Skip to turn 12-19 to see Greninja)
Whenever I send it out I lure in a opponents special wall or force a switch to get free PuP
Also that crit on Mandibuzz didn't matter:
+1 252 Atk Life Orb Protean Greninja Rock Slide vs. 252 HP / 252+ Def Mandibuzz: 268-320 (63.2 - 75.4%) -- guaranteed 2HKO after Leftovers recovery
Imo its not as bad as people make it seem.
Though not that high up the ladder. This team made it higher not too long ago but I swapped out Physical Sylveon for SD Aegislash.
Here is an older one where she starts her rampage around turn 21/22:
http://replay.pokemonshowdown.com/ou-101080206 The Rock Slide flinch though did matter on how long it lasted
Ended up losing but she still did good.