First of all, the first post I made in here (the one you quoted) isn't well put together and does have a good number of holes in it. The second one is more along the lines of what I'm actually trying to say.
I get your point though, while you may not knowledgably have a preferance, your mind may have a subconcious preferance, perhaps one has a better sounding name for example
So you admit that regardless of how little that care maybe, there is always an element of care involved. The simple fact that you've taken the time to think about it shows a level of care you've given to the subject regardless of how small that thought might have been. The ONLY way you literally couldn't care less is if it's something you hadn't even thought about, ever.
but this is really clutching at straws, since it is after all a figure of speech.
As I said earlier, as a figure of speech I have no problem with it, but in terms of factual correctness "I could care less" is actually more factually correct. I'm not saying you should use one and not the other, frankly it doesn't bother me which people use. Just that the one some people claim is innaccurate, is actually the one that is more accurate when literal meanings are being used. Regardless of how helpful you find the information contained in the comment to be, I could care less is more true than I couldn't care less.
So then what about 'I could care less', this is no use as a phrase whatsoever, it can only be understood once it has context e.g 'I could care less but it is unlikely'. Now it is useful as a phrase, since we have an indication of how much you could care.
Now this I dissagree on, my take on the phrase "I could care less" geenrally means that if you were willing to think about it some more, you could explain why you could care less (either verbally or in your mind it doesn't matter), but you don't care enough to think about it any more which automatically puts it very low down in your care-o-meter, it doesn't put it at zero, but it puts it low down. Ofcourse, that's my take on it, and it is a correct interpritation provided that it was said with that meaning in mind, but I think most people that say it mean that they don't care much. So in terms of facts, it's far more accurate than the other saying.
If I just said 'I could care less' it suggests nothing, you could car less than what? how do you judge what they care less than, it is very much ambigious. e.g 'I could care less who wins the football tonight' suggest you care somewhat, but the extent at to which you care is unknown and thus is useless.
Which is true, you do care somewhat about the match, you've thought about it. You've given time to that thought regardless of how much or how little. That in itself is a level of care that you've taken regarding the subject.
As I said before though, I don't really care what is used.