How would Yamato supporting Hood have changed the Battle of Denmark Strait?
Short answerBismarck would have strong reason to disengage from a force carrying Yamato's 18-inch guns, despite the Japanese battleship's 27-knot speed.
NotesThis counterfactual retains the Anglo-Japanese alliance and places Yamato in the force supporting Hood. Yamato's 27-knot speed limits the group's movement, but her 18-inch guns give Bismarck a strong reason to escape. The immediate prediction is disengagement by the German ship.