Holding the Kuban 1943, Good idea or not?

Although most writers state that holding the Kuban was a bad idea, was it really?

The Germans held the area with little armor, some infantry, Romanian infantry usable in such terrain, but withdrew a number of good divisions anyway.
Holding the area means the Soviets can't move naval units into the Sea of Azov.
The Germans achieved like a 4-1 attrition ratio on defence.
It was good defensive terrain. (marshes)

Opinions?
 
I don't know the exact specifics of the situation, but in general terms, there's two factors to this Eastern Front land argument that apply to pretty much any piece of territory there.
  • The reality that by 1943, and especially after Third Kharkov, if the Germans are withdrawing from an area, they're not getting it back. Ever.
  • The skewing of historians by taking postwar claims from German generals of "Oh yeah, we could have totally mounted a successful elastic defense if not for that meddling Hitler" at face value.
 
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