Especially at a christmasdinner.
But with a large group accidents are about to happen, and spilled wine, fruitjuice or freasy food can make a wonderful tablecloth look like it's pulled from underneath a mountain of junk.
Take your plain tablecloth and put it on the table.
Then take either homemade or bought small pieces of tablecloth and put them at the places where you want the plates.
It should be wide enought to cover the border of the table to slightly above the top glass. Long enough the cover the whole lenth of the table.
Make or buy a second set and buy plastic tablecloth of the same size.
Put the pastic under the long small pieces.
And keep the second set as a reserve,