If the copy becomes distracting in the design then you are doing something wrong or they are discussing copy changes. It might be a bit annoying but you could tell them that that discussion would be best suited for another time. At worst the discussion is at least working towards the final goal of your site where questions about lorem ipsum don’t.

Typographers of yore didn’t come up with the concept of dummy copy because people thought that content is inconsequential window dressing, only there to be used by designers who can’t be bothered to read. Lorem Ipsum is needed because words matter, a lot. Just fill up a page with draft copy about the client’s business and they will actually read it and comment on it. They will be drawn to it, fiercely. Do it the wrong way and draft copy can derail your design review.

We shall defend our island, whatever the cost may be, we shall fight on the beaches, we shall fight on the landing grounds, we shall fight in the fields and in the streets, we shall fight in the hills; we shall never surrender.

This is quite a problem to solve, but just doing without greeking text won’t fix it. Using test items of real content and data in designs will help, but there’s no guarantee that every oddity will be found and corrected. Do you want to be sure? Then a prototype or beta site with real content published from the real CMS is needed—but you’re not going that far until you go through an initial design cycle.