He used an expression that is often misused - I could care less vs. I couldn't care less.
But the misused version of the expression is "I could care less", which suggests that one cares at least a little because there are quanta of caring that are smaller. "I couldn't care less" is the appropriate wording for the sentiment. The only problem that I can see is that the apostrophe was in the wrong place, which was likely a typo considering FTP got it right in the followup.
..and with that, it's bedtime for the Grammar Police. Even if it is 8:22 in the morning. They stay up all night, I think.