Tanks aren't that tanky? Amumu with 240armor 168 MR, kennen also gains from kills and so does mf, galio has 286MR and 180 armor and 3k life? Total set of **** masteries? Go see all the jungling guides and you see if those masteries are wrong (will change the point in greed into improved smite). Hard late game why? THey have tons of dmg, life, protection and support.

The tankers aren't that tanky, the support seems to be the most important at getting kills (mejai), totally 0 in good hands for all champions except amumu (with 1 only) leads to really hard late game if a single person dies, Amumu has a total set of **** masteries etc. If you go that way, you might as well try Gragas style of 10 10 10 Masteries which aren't good. Greed is useless and only taken if you don't NC, you don't have much MP, you don't take clarity etc. AKA its useless for most.

Hope it helps