On at least three different occasions we dined at restaurants with friends with the same peculiar circumstances. Usually there were six of us, and when our orders were delivered to the table, one person's meal was "not ready" and would be "out in a minute." Well, it wasn't, and it put all who were served in a position of having to choose between waiting until the last person's meal was served (then their food would be cold) or going ahead and eating with the odd man out left to watch as everyone else devoured their food. (Then that person would end up eating his meal after everyone else was through with theirs.) How do you suggest handling this situation properly and graciously?
If the restaurant personnel would simply keep everything in the kitchen until it was all ready, the problem would not arise. This has happened enough times that I am appalled.
Gentle Reader -- In agreeing with you, Miss Manners knows she is bringing on herself the anguished and angry outcries of restaurant workers about how hard they work and how difficult it is to time a variety of dishes to be ready at the same time.
She agrees with them, too, and sympathizes as well. But she does have to remind them that, nevertheless, that is the business they are in.
People go to restaurants with the intention of dining with those who accompany them. This obligates the restaurant to accomplish the admittedly difficult task of serving each course to them at the same time and clearing each course at the same time -- or to warn them that a particular dish will take longer than the others.
Should they fail to do so, those who received their meals can request that they be taken back to the kitchen and kept warm, while the person whose food is delayed is obligated to say, "Oh, please go ahead and start -- it will get cold."