Rarely have I encountered clients who become furious over word choices, but it does happen. I was working on an ad for a company in human resources, and used the phrase “to complement your staff.” Upon reviewing it, the client changed the largest word in that sentence to “compliment.” I changed it back, and the client took a vertical leap into his ceiling.
He screamed at the designer I was working with that I must be an idiot who couldn’t spell. The designer called me, and I explained that, no, “complement” and “compliment” are two entirely different words, and that in this usage, “complement” was the correct one. It wasn’t a matter of preference, but one of accuracy.
He insisted that there was no such word in the English language. Even after being presented with a dictionary excerpt, he continued to insist that I was wrong and the word just didn’t exist. For some reason, I never had another opportunity to work with him.
Part of a copywriter’s responsibility is ensuring that a client is presented in the most favorable light, and making sure that the right words are used is a critical element of that. I’ve had battles with clients over other words and (especially) punctuation, in which the clients who were involved seemed to think I was simply being difficult when I insisted they do things correctly. Nope, just trying my best to make them appear to be intelligent and literate. In theory, the better they look, the better I look.