I haven't, but I know that it's possible to do something that either changes the final boss or the ending if you do this at the end of the game.
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R, Japanese on the next line.
アープ戦の前に、ティアの選択肢で、信じられないを選択すると(おっとっと、あぶないあぶない)。
Translation: Before the fight against Earp, when you select Unbelievable from the Tier options (oops, dangerous, dangerous).
That was one of the clues on Morokuma's text game board that he posted himself so I'm guessing that it has to do with the god you mentioned.