It concerns me though when a programmer “could care less” about the difference between an expression and its negation.

Im not because you can treat it as a threat rather than a simple statement.

"Keep talking and I can care less than I already do."

To me, "could care less" is perfectly readable, because people writing that mean "couldn't care less" 100% of the time.

Now, could (or couldn't) "careless" bothers me.