If you want to compare the edge holding ability and the cutting ability (some steels will just plain get sharper than others), then I would say a lot would depend on the skill of the maker, the heat treatment, and the type steel used.
A good steel knife, ATS 34, 154CM, BG42, S30V, and others, properly heat treated would out preform a lousy made Damascus blade, and I am sure there have been some lousy damascus blades turned out.
Conversly, a properly made damascus blade, using suitable steel, would out perform an improperly ground and heat treated blade made from the steels listed above.
If both were properly made, using a suitable steel, I doubt that you would be able to tell much difference in performance, although I cannot speak from experience, except that I have used and seen used many ATS 34 and 154 CM blades, and I have no complaints.
From what little I know about damascus, it can be differential hardened, therefore it should be more flexable that a ground (stock removal) blade.
Of course, if the knifemaker knows what he he doing, some of the stock removal blades can also be differential hardened, but I don't know if any of the steels that require heat treating in a controled atmosphere furnace could be differential hardened.
