I once got into what I would advise my younger self against was an argument about an aspect of Lord of the Rings and I quoted Tolkien himself to prove my point and the guy I was arguing with said, "what does he know? He only wrote it."
A lot of people swear by this whole "death of the author" philosophy because it let's them ignore the literal stated intent of the author in favor of whatever pet theory they have. Which is fine, but you can't use it in a debate about theories about the work. There isn't a right answer to what you want to believe, but there often IS a right answer to what the actual author actually intended, especially modern authors in the age of information.