I think you can assume decent shuffling for the sake of the problem. And with cards dealt around, you don’t see two cards in a row. You’d have to be pretty bad

I think you can assume decent shuffling for the sake of the problem. And with cards dealt around, you don’t see two cards in a row. You’d have to be pretty bad to get usable info from cards at position n and n+4 being the same suit. edit: People can be pretty bad at shuffling though. Overhand shuffles are awful and info would be available. But I think this game naturally sorts the cards pretty well by the end of gameplay, so even the method proposed before me would be vulnerable to info from bad shuffles.