Destroyer harassment hurt Bismarck chiefly through crew fatigue

Did the destroyers harrying Bismarck overnight do more damage to secondary systems or to crew endurance?

Crew fatigue was probably the greater effect, though 4.7-inch fire likely damaged some secondary equipment.

The panel allows that 4.7-inch fire probably damaged secondary systems, but identifies exhaustion as the greater effect. The destroyers denied an already damaged ship's crew the sleep and recovery needed before the final battle, showing how harassment can reduce combat effectiveness without scoring a decisive hit.