Altho the timing is perfect for a Parker based Switch..I highly doubt Nintendo went with a custom made chip of the newest architecture that would cost tons of money.
What is more likely is that they modified the older Maxwell X1 architecture.
Nintendo has never really choose to go cutting edge with exception to the gamecube and even then they went with tiny discs...
For the record the Wii U is 45nm, Tegra K1 28nm ( 8 watt power consumption), Tegra X1 20nm (roughly 10 watt power consumption and 15 TDP), and Parker is 16nm..
The point is that it would probably cost less for nintendo to go Pascal since it's on a node that everyone is using now, instead of going for an older node that is being phased out. It's a bit like the issue of the WiiU, which costed a LOT to make despite being archaic exactly because it was so customized and non-standard. Going standard would save a lot for Nintendo, and unless they made some very strange contracts so that it cost less for them to go 20nm, i think they'll go Pascal.
It also save about 40% in power saving at similar performances, so there's that too. TDP saving are extremely important for a portable.
Amazing specs, I would have never thought Nintendo would make a system with up to date hardware these days.
Aside from the fact that it make it looks like this run TWO parkers (which is not happening as Nintendo said there's no additional hardware inside the dock, it's also generic as all hell. Parker-based is probably a given , but Parker based can be from 0.2 to 2 Gflops easily so it doesn't mean a lot.
15W isn't totally unreasonable for when the system is docked. But it's completely unreasonable for when it's portable.
Possible, but you have also to consider that if it has to switch seamlessly, the main unit can't run hot. I mean, it's not impossible given that the shieldTV never run hot with a simple fan at 15W TDP and very similar size, but when you factor in the screen that gobble a bit of that size and Nintendo being conservative... i think it will be a tad bit slower even in the best of cases.