Nintendo would be much better off just building some kind of proprietary dock for an iPad Pro and coding for iOS. They could then sell their games (as cheaper versions, "mobile" alternatives) in the app store to anybody with an iOS device and enable the full games to be played when the dock is attached, perhaps adding to the experience with their trademark Nintendo gimmicks and decent ergonomic and kinesthetic design prowess, exemplified by the N64 and Wii controller designs.
The revenue from iOS would be massive, and the iPad Pro already has a far superior cpu/gpu to any Tegra, including Parker. The iPad Pro already has 50+ Gbps memory bandwidth, it also has a manageable TDP and has been tested not to throttle (as all Tegra chips are notoriously prone to high power budgets and throttling).
This is nothing short of an idiotic move by Nintendo, but they are a company that has long been notorious for ill-conceived hardware decisions. Case in point, shoving some kind of 12 watt TDP automotive part they probably pulled out of a Tesla scrap yard into a "handheld" or tablet and expecting it to perform. They will down clock the %*#@ out of it and it will still draw too much power and perform like garbage, expect about what you got in the WiiU.