How It was Explained to me:
totem has a master List, of Random Cards created back when the Carousel was created..
then as new cards are published they get added to the list..
Each member starts out at Spot One on the List..
you get a selection of Cards that you Don't Already own, but selected in order from that master list..
Your Spot / location on the List is saved, and then new cards are again selected off the list from the last location you were at..
a Corrupt file or deleted file, can cause you to get stuck, or start over again on the list..
Once you reach the end of the list, it repeats.
This is why, when you See a Card that you Have already seen, the list of cards will be Similar to as they weer the first time you Saw them..
Cards you don't own, selected from a master randomized list.
I don't know if that is how it still works, or Not, but that is what was explained to me when it first went into use.