A lot of markings on the back of sleeves are not caused by wear of shuffling but by rough movement when putting a card in a sleeve. This can be prevented easily and allows you to use your sleeves much longer for tournament play! Watch the video to see what to look out for exactly.
Do you want to know if you can play that wonderful altered card you got? What about that misprint you traded last week? Is my deck fine to play at this weekend tournament? Miky clears out all our doubts here! (And, well, ask the Head Judge!)