Good question Kimon.
And thanks, raeanne, for working out the answer. Makes my head hurt to think about it. As someone said, a bazillion here, a bazillion there, pretty soon it adds up.
So, with a number followed by 115 zeros, without factoring in all the number of cards in a spread as nexyjo suggests, and if each card represents a range of possibilities, why are reversed cards needed at all?
I am neither for or agin reversed cards. With my ancient Aquarian deck, the book I had recommended reading reversed cards so I always did.
With the Robin Wood deck, in her wonderful book she says why bother, so I don't use reversed cards.
And I don't believe readings with the RW deck have any less depth than with the A deck.
Still, with all those googleplex numbers, it should be amazing that cards so often repeat. But it isn't. Actually, in real life, it seems coincidences abound. In fiction if a writer uses coincidences to resolve plot problems it is unsatisfying and amatuerish, but in real life coincidences happen ALL the time. I'm sure there is a field of math that covers this, and raeanne could probably explain it.
So, shuffle-mix-shuffle the cards and lay them out again, but don't be surprised if the same cards come up. Must be a message there, huh? Oh, how I wish I could really read that message. But in spite of those 115 zeros, the coincidence doesn't surprise me.
Talisman
Who counts on his fingers.