I felt that this kind of instruction was more related to story than to gameplay. Story-wise it wouldn't make sense that you're not told what to do there. That's kind of a theme for all the "boss" battles.. there's another character who knows more about the boss than you do. It also gives sense that the battle is more of a collaboration rather than you just figuring out some way to kill it.

I don't think they were worried about people not figuring out what to do. In other parts of the battles you have to figure out much harder stuff for yourself.