Are you kidding me?
To achieve what CryEngine 2 is/has achieved, you need to know your sh*t. Crysis has a lot more detail than COD4. A complete dynamic, vast open environment with foliage as far as the eye can see. Not to even mention, completely dynamic winds which affect all the foliage and volumetric clouds. CryEngine 2 is a monster compared to COD4 engine, have you even looked at the Sandbox?
By old habits I'm assuming you're talking about Farcry? Many of today's Engines are still struggling to achieve what CryEngine has. It had HDR way before most gamers even knew what it meant.
Besides, you cannot compare 'optimisation' of CryEngine 2 with a propriety engine.