Denmark Straits, HMS Hood and Prince of Wales meet KMS Bismarck and Prinz Eugen. The RN cruisers Norfolk and Suffolk are in the area, but too far away to have a good view of the battle. They report a few garbled radio dispatches, and four large visible explosions over a period of 10 minutes. Rushing to the scene they find little wreckage and only a handful of survivors. The survivors know little of what happened.
How might this outcome affect the war, naval theory, and history?
I consider this to be a very low probability but still possible result of the battle.