Now you're just grasping at straws, seriously. Provided the next 3DS revision will have a changed shape, it would require a new Circle Pad accessory for it. Ergo, the new revision is likely to incorporate the stick natively, because there is no point in making two revisions of the exact same add-on. Likely being the keyword.What fact are you talking about? You're assumption that a 3DS revision will need two analog sticks or that past games needed it? Because those are opinions.
Past games on the Gamecube needed two sticks, on the Wii it was a comfortable option for some, but nevertheless, both sticks were used in compatible games.