Client: I noticed you changed some of the text.
Me: I made some slight grammatical changes, yeah. Mostly adding commas where they should be, etc. Is that a problem?
Client: Yes, it’s a problem. I want you keep the text EXACTLY how you receive it. I hired a professional grammarist and there is no need of any of your input.
Given that “grammarist” isn’t a real word, I kind of suspect this person’s credentials.