I have a hard time sympathizing with a student who cheated for 3 semesters then hit a brick wall when they finally can’t cheat. A student struggling with the material is one thing but a student finally getting caught after cheating through three semesters is another. “Dum dum” is being kind IMO.
I'm not using the word dum-dum to their face.
And when you see them several times a week for a semester, the sympathy grows on me at least. The people who don't show up before the exam and fail miserably, they're a little harder to sympathise with.