Of course it most likely goes back to the good old days of games on Xmas Day followed by the return fixture on Boxing Day! Before most of the posters on here were Rams no doubt!
As an example we played Bristol City at Ashton Gate on the 25th Dec 1957 losing 2-1 but won the return at the BBG on the 26th Dec 1957 5-2!
Fancy today's Prima Donna's coping with that, poor things!