That is exactly what I'm saying.Consider the following:
I am capable of caring about any given topic on a scale of 0% to 100%. 0% means I don't care at all, and 100% is absolute devotion.
Let's say you buy a new pair of shoes. You're in love with them and want to show them off to everybody. We run into each other at the porn dungeon, and you immediately launch into a story about your shoes. I can make one of two declarations.
1) I could care less about your shoes.
2) I could not care less about your shoes.
Assume that I care 0% about your shoes. I don't care about them at all, in other words.
QUESTION: Can I care less than 0% about them?
a) Yes, I can care less than 0%.
b) No, I can't care less than 0%.
c) What are you, an idiot? Of course I can't care less than 0%. Didn't you see where I said the scale goes from 0 to 100?
ANSWER: Both b and c are correct, although c is the preferred answer.
Having established that I can not care less than 0%, and I care exactly 0% about your shoes, then it stands to reason that I could not care less about your shoes.
For the record, if I cared, say, 10% about your shoes, then it would be correct to state that I could care less about them. You see, it is possible for me to care less than 10% about them.
With this logic in mind, you can see two things:
1) "I could not care less" inherently means that I care 0%. If I care even 1%, then I could care less and the statement is false.
2) "I could care less" could mean that I care anywhere from 1% to 100%. Such a distinction is practically meaningless.
For completion's sake, "I could not care more" would mean that I care 100%, whereas "I could care more" indicates anything from 0% to 99%.
If you're still not grasping this astonishingly simple concept, I could probably make a flow chart or something.