That was minor compared to the Old God influence in WotLK and Cataclysm. MoP was not an Old God expansion. The Sha were merely an Old God's farts. And Garrosh's empowerment byY'shaarj's heart was basically irrelevant. It just made him look retarded.
Did you honestly think I didn't know about these plot elements?
Child, sit down.
They were minor elements and did not make the theme of MoP. The theme of MoP was pandas, Pandaria and their culture and everything that was on it, and the escalating faction war between the Alliance and Horde.