I guess I'm not explaining my point well enough. Let's try more structured and concise.
The problem isn't "pain is an experience". The problem is that the following are 4 very different things:
1. the experience,
2. the MEMORY of an unquantifiable, undescribable experience
3. the ability to COMPARE memories of such unquantifiable, undescribable experiences
4. how you REPORT such
Even going "pain is the experience" doesn't cover #2, #3 and #4 at all.
And the fact that we're crap at #2, #3 and #4 is well proven by now.
E.g., since theprestige brought up colours, that will do nicely to illustrate #3. Because there are actual studies that show that if you don't actually have a different word for different hues, i.e., you can't remember them that way, you absolutely suck at telling whether the colour you remember is the same as the colour in front of you now. As in, if you go to some people who have no different word for "orange", they just call it "red", and you show them an orange card and a range card, sure, everyone will say it's not the same colour. It's a different shade of red, obviously. But if you show them an orange thing today, and tomorrow you show them a red card and ask them if it was this colour, most will say, yeah, it was exactly that colour.
And that doesn't just go for tribes who lack such words. In the very modern western world, virtually everyone who doesn't know burgundy as a separate colour, makes the same confusion between burgundy (#800020) and red (#800000). In fact, a lot pretty much feel like #800020 is THE natural red, a lot more so than the actual #800000 red. Yeah, they can tell it's a different qualia if they see both right now, but they suck at comparing it to the qualia they remember from yesterday, if they can't put a different name on it.
E.g., your memory of a subjective sensation being unreliable and changeable depending on what you want to believe, is the whole POINT of the classic cognitive dissonance experiments. You know, the one where where you have to turn a knob by one degree every X minutes, or to turn pegs in a peg board for an hour, or such. Yeah, boredom is the experience too, there is no quantifiable value, bla, bla, bla. But if at the end of the day,
1. my experience may be that I was bored out of my skull, but
2. how I REMEMBER it after the cognitive dissonance kicked in might be that, actually, it wasn't too bad
And if we add what we know about reporting other things,
4. how I REPORT it may be that it was actually a nice and educational experience, e.g., if I get the impression that that's what the guy polling me wants to hear, or that's what the other group members are reporting, or any of the other KNOWN factors that distort such reports.
So you can stop hammering on "but the pain is the experience." Again, that covers #1. It does NOT cover #2, #3 or #4 AT ALL.