Well I happen to know for a fact that isn't true. I know some people have had issues with the encryption and things like that on PS3, but there are editors available that decrypt and re-encrypt PS3 files with relative ease. I've managed to do it even though I don't know jack about hex editing in detail, but what I do know is that one in particular - Bruteforce Save Data makes it possible but it's output is a different type of file than the Xbox 360 programs use for editing.
I was really just hoping someone who knows more about it generally would be able to tinker with it and simplify it for us "for Dummies" users, lol.