...in a fine-dining establishment especially, though I actually believe this is Serving 101 and should be taught, and expected, in every restaurant that has table service:

Every table in every restaurant has (or should have, if they know what they are doing) a "fixed point" for taking and delivering the meal orders. Or, you can think of it as each position at each table is "numbered". Thus, regardless of who takes my order, or who delivers it, there will not be a need to ask "and who ordered the Coq au Vin?". The only time that there will be a problem is if the diners change seats after ordering. And really, how often does that happen? If it does, I am thrilled to apologize to the server for moving when he/she serves the food to the "position" that ordered it. And if you think it is too difficult for a server to have to remember this information, a simple chart can be made to "help" them. I did it without a chart when waiting tables in the mid-seventies, in a restaurant that seated 350.

Last year I ate at a highly-rated and expensive restaurant in downtown Seattle (excellent food but I will not return for this reason, especially after complaining to the manager and getting a "well, sorry, it's hard to get good help thse days") and the server, who both took the order and delivered the food, still had to ask who got what. At > $50 a head, food only, this is completely unacceptable.