That isn't what is going on here. If AMD sold two X3s, one with three actual cores, and one advertised with a 4th, locked, core (along with a higher price), all of a sudden things have changed. Why advertise the 4th (locked) core if it shouldn't change my expectation of the product, and why charge a higher price?
I'm not arguing that OP should RMA his CPU, nor do I believe he should be allowed to. I understand what specs are, and as long as his CPU operates with those specs his CPU is fine. That being said, I dislike how semiconductor companies have recently been selling OCing as a feature -- a feature as you state they offer no guarantee on.
I understand people can sometimes feel far too entitled to things these days, but paying extra for a product that advertises the ability to overclock (we're talking about the CPU, NOT the motherboard) and then fails to do so (of course, technically it IS unlocked) is not a false sense of entitlement. The manufacturer has IMPLIED you will be able to do something (up until the point where they'd actually be legally obligated to provide that level of performance) in the hopes you'll pretend their implication is as good as a guarantee. I agree with you that people shouldn't actually expect the implied levels of performance -- but I believe it is dishonest marketing.
All of the above, from the hypothetical case of AMD selling two differing cpu's with the same specs but for different prices and different "locked" features, to the topic of selling unlocked CPU's that may or may not be overclockable, all falls under the purview of "buyer beware".
Marketing's job is to sell the "implied" while limiting liability to "the fine print". Yes?
I can't tell if you are just taking exception to the notion that Intel's unlocked chips may not be overclockable or if you are simply against the entire industry of marketing, the use of fine print, and buyer beware of trying to get something for nothing.
There's a school of that
you can't scam an honest man. The idea being that it takes a dishonest person who is out looking for an unhonest way to get something for free or on the cheap to unwittingly fall into a scam offering (implying, via marketing) as much.
Core unlocking is like that, it is a "feature" offered by mobo makers (and AMD could have put an end to that immediately, if they really wanted to, but they let it go since it obviously netted them more coin than otherwise) which for people looking to get something for nothing (or for less than paying the price of a fully functional cpu) was great, except for when it didn't pan out on every locked cpu...
Same with overclocking. We are all looking to get more out of what we paid for versus paying more and getting exactly what we paid for. Sure the marketing here is implying we can actually get away with it, that's why mankind invented the industry of marketing.
But let's state the obvious, inventing the industry of marketing would not have resulted in much were it not for the fact that there is a whole world full of people out there who are ready and willing to listen to it.
Marketing works because people are receptive to the idea of getting the "implied" when they know they are only buying whatever is laid out in the fine print. Hence the reasons we all know what the term "fine print" entails, we are all keenly aware of these distinctions for the very reasons the distinctions exist.