When organizing a potluck dinner exercise the right of controlled chaos otherwise the table is going to look like a local food festival. Ask someone who you know for sure is a good cook to bring a main dish, a meat or a vegetable and I'm not talking about a String Bean Casserole, after an hour it looks like Casserole a la Mush. Don't ask a friend of a friend to bring anything to eat because no one may be able to vouch for their skills or the way they run their kitchen or their chicken. Did they wash it well? Did they wash it at all? On second thought maybe you should cook the main dishes and let others bring important sides. Ask for one fruit salad, a cake or a pie and ice cream.
Consider food allergies, let guests know what's on the table and if need be, point out what a particular dish is or isn't made with - no nuts, for example. Use your own bowls and serving platters, get rid of the foil pans , you don't want your guests eating out of vats.
If you don't like potluck dinners don't accept the invitation or say that you'll stop by for dessert or drink and offer to bring something. No need to point out your germ phobia or that you happen to know that one of the guests keeps a less than pristine kitchen.
I don't think Yvette or I have ever thrown a potluck dinner. Even though most of it is outsourced, it's still a lot of work and risks are great. We like to cook and turn into control freaks in our kitchens.
Food is love. It brings people together, it's an opportunity to show friends and family how much you care, how you want them to enjoy the best you have to offer. There's nothing wrong with the concept of potluck but in this world of killer tomatoes and spinach, maybe it's time to fine tune it. Maybe it's time to not push your luck, at least not at dinnertime.