You would be wrong about that. Consider that with MVC you don't have the entire, massive Page Lifecycle thing and a control tree to parse and walk through (decrypting ViewState, assigning control values, and so on). MVC is actually faster than ASP.NET WebForms.

But it's faster in pico seconds (meaning it's immeasurably faster) and if you're worried on that level - you're doin it wrong :).