Here here! As my intro to proof professor always said about "obviously" and "clearly": If it's so obvious, it should be easy to show, and if it's so "clear", why did you need to tell me it was?
EDIT: And less snarkily, obviousness is highly path dependent. What is clear as day to you as the author, who has been working on the proofs for the past 6 months, is rarely obvious to a new reader.