How can you be so critical of a stranger's work given that you haven't even seen it?
"that reason was most likely because" -> Bear in mind you do not actually know the given situation.
"that reason was most likely because" -> Bear in mind you do not actually know the given situation.
If the document really was so clear and error-free, then why would the boss try to "fix it"?
People often apply nonsensical standards to things.
If it was truly a manager, where the main role of their job is to manage the performance of their employees, then they failed here.