Nintendo's Circle Pad Pro attachment for the 3DS seemed, when it was first revealed, to be something of a panic move, made in response to the handheld's then-poor sales and the positive reception received by the competing PlayStation Vita (much of which centred around its two wonderful thumbsticks).
But just how last-minute was the peripheral? Well, Nintendo's own Masahiro Sakurai, director on Kid Icarus Uprising for the 3DS, has told Official Nintendo Magazine "I didn't know the specs of the Circle Pad Pro, or what it looked like, until Monster Hunter 3G was announced, so we weren't able to do anything big with it in the time we had."
Monster Hunter 3G was announced in September 2011, and the attachment went on sale in Japan in December 2011. The 3DS itself only went on sale in Feb/Mar 2011.
If Sakurai is telling the truth (and the way he hedges why the Circle Pad Pro doesn't really help Uprising's controls suggests he is), shouldn't he have been told? I mean, he's one of the most senior developers at Nintendo, working on a game (with a 3D camera!) that would seem ideal for the peripheral. The fact he's saying this seems insane.
Either Nintendo's internal communications are woeful, or they threw this thing together real fast.