I'd say look at concept and storytelling as on a spectrum. 0-10 if you like. Generally you get a higher score the higher both are, but you can have a okay story with a good concept thats still compelling, or a really well told story with a basic concept that just charms your pants off.
Now, if the concept is bad it's going to be harder for good writing to cover for that, because the two are linked. If the concept is the idea, the storytelling is the communication of that idea. If the idea is bad, you're communicating a bad idea. You're getting into murky territory. (which isn't the same as a flawed concept, because an idea can be flawed and still have merits!)
Maybe abstract, nonlinear, and generally art-housey type works come closer to this. These tend to be works that are dominated by concept and not necessarily about conveying a cohesive story. At least, not in a conventional sense.
However it still takes skill to communicate ideas, and I maintain that storytelling could be translated to the communication of your concept. Which is just to say the two are inherently linked.
(sorry if I said anything the repeats or over laps with what others have said, I originally read replies a while ago, and just happened to have a though when the board popped back up! lol )
