I recently played with someone who told me I was lifting my cards high enough for her to tell the suit. I thanked her, especially because she also kept informing me of the action of seat 9 while I was in seat 1, blocked of sight by the dealer. All depends what type of person you are. I used to try to exploit it but stopped after the plan backfired when I thought I saw something that wasn't. I'm not above keeping a secret from someone I loathe, however. If some imbecile with the manners of your ex's PTSD afflicted tabby is forgetting the backsides of cards look the same for a reason, then steal his gambling rounds. If a person seems decent, consider the karma.