We haven't had the same very good roster. When TFC won the cup, the bonuses that kicked in forced TFC to shed some key players (eg Beitashour) that were necessary to play Vanney's system. The replacements Bez got were duds and Curtis hasn't addressed the issue yet.
So either Curtis gets the players, Vanney adapts to a less than ideal roster (which I think he's capable of but he's stubborn), or we get a new coach. I'm sure Curtis has his own guy on his rolodex ready to replace Vanney so Vanney's tenure isn't completely secure.