What if the Kriegsmarine had attempted a losses-be-damned surface-fleet dash against D-Day?
Short answerThe force would probably have been destroyed by the layered Allied sea and air defences before it could break up the invasion fleet.
NotesGerman capital ships first had to leave Norwegian waters, find fuel, and survive layered interception in the Channel. Even if they passed mines, submarines, and motor-torpedo boats, the 10th Destroyer Flotilla and bombardment battleships would meet them before they reached the invasion fleet. The likely result is heavy German losses without a realistic path to the landing area.