Assuming you're correct that the commenter is unaware of their communications deficiencies, then as much of your confident criticism should be directed at a man

Assuming you're correct that the commenter is unaware of their communications deficiencies, then as much of your confident criticism should be directed at a manager who would silently change a spec sheet for some reason, and not coach the employee on why that was needed. 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.