As a professional service provider, our company provides a customized IT enterprise solution to a customer. One of our deliverables is a design document, which describes the components at a high level.
The project manager of the customer's company reviewed my document, and made some grammatical changes that I do not agree with. He told one of my colleagues (who is in charge of communications and has no technical background) in a phone conversation that one "should never trust the English from an IT person".
While I admit that an average local IT person here does not have a good command of English, my past experience is very different than that of other locals. Long story short, I am fairly confident that my English ability is superior to his.
How should I approach this customer's project manager, if this English issue comes up again in the future? What should my game plan be? How can I respond professionally? The current project is already underway, and my boss may arrange future projects with this customer, so a good relationship would certainly benefit everyone.