Headline in a Dell ad in today’s newspaper reads “LESS HEADACHES, MORE HELP.”
One would expect better of their ad agency, but as obviously they need help, I suppose Dell should hire a staff grammarian, eh?
Mundane, pointless question: If I had three headaches last week, and three headaches this week, and the three I had this week were all less intense and shorter in duration than those I had last week, could I correctly say I had less headaches this week?
Sure, you could say that. 
It would be better to say “I had shorter, less intense headaches this week.”
I’m sure they would experience less problems if they did. 
Meh, if I decided to care every time someone said “less” when they meant “fewer” my head would have already exploded. Care less, live longer, is what I say.
This sounds like a job for…
Conan the Grammarian!
[sub]And his faithful sidekick Punctuation Boy.[/sub]
The less/fewer things is one of the most common mistakes, as far as I’ve noticed. I must see it in ad copy and hear it on TV a couple times a week. It used to drive me nuts, but I’ve become accustomed to just shaking my head and muttering ….idiots.
So you not only could care less, you actually do care less!
Or you could care fewer and live more.
The grammatical confusion built into Windows is worse. When you use a computer, are you in the first person, as in “My Computer”? Or the second person, as in “Where do you want to go today?” Or the third person, as in your username? Can you think of any other entity you communicate with that interchanges all three of these? This example of complete confusion of the personal pronouns might just be unique.
IT WAS A HEADLINE! The rules for headlines are different, since they are constrained by factors that have nothing to do with grammar, but which are much more important that good grammar.
LESS takes up less space that FEWER (the W is a real killer as far as fonts are concerned).
Changing it to “fewer” might have required a smaller point size, making it less prominent, and the point is to get the message across, not use great grammar.
It was part of an ad, though; it wasn’t like it was a newspaper headline.
I’d be more impressed if they hired decent engineers and technicians.
More in line with the OP: my favorite supermarket has, over the express line, “12 items or fewer.”
Right! However, I think it’s the indecent ones who write the ad copy.