Usage and Grammar
Q. An author insists that superlatives must always be preceded by the because there is only one thing that can be the most or best of something. I think that rule is bogus. For example, “The weather is hottest in July” seems grammatical and much more natural than “The weather is the hottest in July.” Am I wrong, or is this just another zombie rule?
A. Zombie rule. You can see at CMOS 5.161 that most of the examples omit the. If you are pressed on it, ask your writer to provide an authoritative source for his rule.