I could be wrong about this. I'm not a professional game designer or anything. But it would provide a logical answer as to why all the patches will be released at the same time.
As to the debate about beth developing for PC versus console, all I can say is, if you had a chance to make hundreds of thousands off a game as opposed to making millions, what would you do? The answer is obvious. Develop and cater to consoles. That's where the big money is. My only complaint is that they can adjust the UI for the PC version to something less clunky, but they don't. Not sure why, other than the reason I stated above: it's easier to patch one game and release the patch to every machine than to patch several games and chase the same bugs on every different platform.
That said, even if they all used DirectX, and the same version of it, you're still off-base. DirectX is the interface to the hardware, but the implementation underneath is different for each platform. You can treat DirectX as a black box for little hobby projects most of the time, but for a game like Skyrim, or any game anybody would ever pay money for really, there are going to be differences in the implementation of the interface that will leak into the code making use of it which will need to be accounted for in targeting each platform. As such, no, it is not a given that a patch for a particular issue on one platform will solve it for each platform. Often that might be the case for non-graphical issues concerning game logic and such, but there is so much uncertainty in what goes on underneath the hood that you really can't say for sure if you haven't looked at the source. And even then you'll be wrong most of the time
If you don't think developers at Bethesda Softworks are working 80-hour weeks right now, think again.
In short, programming is hard.


