That still counts for experience, doesn't it? It's not like the UK team hid their experience with the console from the Frankfurt team...The Haze dev team only did the MP section while the main Frankfurt studio who has never had any experience on PS3 development worked on all the porting etc. So yeah, it's their first attempt.
And it doesn't change the fact that it was actually their first attempt with the X360.
Its the PS3 version that runs smoother (during gameplay).
I think that you're mixing "during gameplay" with "during heavy load instances", which probably counts for a fraction of the actual gameplay. At least from the gameplay samples that we have we can see a smoother framerate average on the X360.
But that's not even relevant to my point. My point was the Crytek catered to both platforms and each has it's own advantages and disadvantages.
They didn't go for "platform parity" which basically means that you play for the lowest common denominator and not using any advantages that each platform offers, and they didn't go for a "port" where one version is clearly superior in all aspects to the other. IMO this shows they they put a lot of effort into both versions.
More then that, the fact that both versions can sometimes have a problem of keeping up with the heavy sequences can at least hint us that Crytek didn't compromise the PC gamers with Crysis 2. The easy solution would have just been to tone down these sequences (smaller encounters for example), but they decided to keep them the way they are.