The Blackburn's value as a fleet spotting aircraft

Did the Blackburn provide any useful naval capability?

Yes; it was a very good reconnaissance and fire-control spotting aircraft if fighter protection kept it airborne.

The Blackburn was a strong reconnaissance platform and one of the Royal Navy's best fire-control spotting assets of its era. Its ungainly appearance did not determine its usefulness. In a fleet action it could improve the speed and accuracy of bringing gunfire onto target. That contribution depended on fighters keeping the vulnerable aircraft alive over the battle.