Watch, look at the current support for the CPP. Only ONE, Nintendo title has some remote form of support for it. Now look at CAPCOMS, line up. They have atleast 4 games coming out for it with support. Why do you think it is that RESIDENT EVIL came packaged with one, when no other 3DS game to date has. When we first heard of the CPP, it was in a JP article on MONSTER HUNTER. Why is it that the CPP is only available at ONE retailer in the US? I think its safe to say that Nintendo wasn't trying to admit anything, it was just so either, Capcom wouldn't drop support for titles like MH or RE as 3DS exclusives or so that people would shut up about the second circle pad. I think it was the former of the two.
Oh, and I honestly dont think anyone outside of the hardcore (and even then only a fraction) would buy a new 3DS just because they added an extra circle pad.
With respect, the argument that "only a few games support it, therefore it's not needed" doesn't really work. Of course only a handful of games support a clunky add-on whose functionality should've been in the native hardware in the first place. They don't want to go to the effort to design extra control schemes that only a few people will use. Or else, for all we know, a bunch of developers aren't making games for 3DS period because of the lack of a native second analog and developing for the Vita instead.
Consider Ubisoft. Last year, they were going to make an Assassin's Creed 3DS game, but ended up canceling the game for various reasons. And then this year the Vita comes out and guess what? All of a sudden, Ubisoft makes a Vita-exclusive Assassin's Creed game, and still no word of a 3DS title. See, they were interested in the 3DS when it was the only next-gen handheld available, but the moment another one came out with dual analogs (in addition to being more powerful), they went for that instead. How much you wanna bet the lack of dual analogs was one of the deciding factors?
Also, you say that Nintendo "wasn't admitting anything," and then proceed to say it was just to shut consumers up, and to keep Capcom from dropping support. Except if those reasons are true, then Nintendo IS indeed admitting they made a mistake. They're admitting that enough customers were going to be pissed at the lack of a second analog. They're admitting that at least 1 third party would possibly drop support for 3DS games if there was no second analog. So yes, the very existence of this first party add-on, regardless of how widely available it is, proves that Nintendo knows it made a mistake.
And as for "only the hardcore would buy a 3DS with a second analog built in" bit, I don't buy that for a second. Have you seen how many people are practically throwing their money at the screen for the XL, even when they already have 3DSes? Heck, I know at least one other temper (looking at you, Midna) already sold their 3DS on the spot to prepare for the XL. And aside from that, you have many new consumers who are all of a sudden interested because of the XL. It would be the exact same way for a 3DS with a built-in second analog.
Anyway, I'll stop there cuz I don't want to derail this thread anymore.