I believe his point was not that one should go with an explanation for an unknown that does not make sense. His point was that speculative explanations and extrapolations by fans are not the explanations provided by the source. There could be five cool ways to explain it and a hundred not cool ways but the underlying fact is that the lack of explanation is in the source and jarring.
"Throwing in these speculations and extrapolations it could make sense" is different than "It makes sense as presented in the book I am reading."
Bingo. I was saying my incredibly bizarro method of explaining it was equally valid as any other method of explaining it. Giving a long detailed description on how you think Lathander changed, me saying "He did it because he likes doggies," the similarity there is that we're both equally valid, which is to say that we aren't valid at all.