You said, ” For example, if I look at a playing card, she can tell me what it is, not just one, but the whole deck.”
Can you do the following experiment?
You pick up 10 random cards from the pack without looking. You should look at just one card within those 10 cards. Then, as I understand, she should be able to tell the identity of all 10 cards that you have in you hand?
If so, ask her to write down on a piece of paper the identity of the 10 cards. Then you look at the 10 cards and write them down too. Then compare whether they match.
Do you need to be face-to-face to do this or can you do it over the phone too?
It would be amazing if she can do it over the phone, even if you are looking at all 10 cards that you are holding.
May be I did not understand exactly what you were saying. If I did, then that would be a good experiment to do.