Miss Manners: How do I tell guests not to bring food without offending them?

DEAR MISS MANNERS: How does one diplomatically, yet adamantly, state that guests should not bring a dish to supplement your holiday event?

I’m frequently asked, “What can I bring?” I always reply, “Your good cheer and appetite, please!” Inevitably, friends will show up with their award-winning dish and promptly put it on the serving line.

Unfortunately, there is the potential that their contribution is tainted -- and being the host, the unfortunate results are on me. The well-being of my guests is essential.

GENTLE READER: The idea that private dinner parties are always done cooperatively has now become so firmly ingrained in the American mind that it has taken on a whether-the-hosts-like-it-or-not urgency.

And this goes double on holidays, when cooperative meals are so common that n