Games are Art. Art invites Critique, it can't escape it.
I agree with the idea that Detective Mode isn't a very good game mechanic. I didn't play the whole game in detective mode but I felt that it was basically like pressing L2 to solve every puzzle.
Yeah, I tend to use it alot. I don't consider it cheating, but it feels like, as Yahtzee points out in Zero Punctuation, an acid fever dream. And it's ugly.