What is the significance of a red cross on a Combined Strategy Deck card, bearing in mind that only the top card of the Deck is ever revealed|?

I would say if you draw the red cross then you can draw another card but it cant be from that deck.

also it would allow the deck to play like a normal deck if it was ever used for one side eg. if the germans had the deck all russian cards would be removed and then it could function like a normal deck.