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I've said it before even way before all these leaks, if making a hybrid Nintendo's "gimmick" is going to be that it's a portable that you set down on say a table and it "invites" people to gather around and play together.
This will by Nintendo's "answer" to anti-social gaming (ie: people walking around with their head buried in their phone or VR). It's a very Nintendo-ey thing to do.
To have the break apart controller thing function for multiplayer the d-pad on one side is going to have to be used as buttons. Unfortunately there doesn't seem to be a way around that.
I still also think Nintendo's old Micro VS. System is partly a design influence here ....
If two players were able to play this thing back in the day, NX's bigger HD display should be a lot better, lol. But I think the break apart controller is for multiplayer in a pinch, not every situation is going to have to 2 NX units laying around and Nintendo wants people to gather and play together, so the two break apart controllers have to be able to accomodate that.
It's also possible that perhaps the NX can stream to local displays ... like it could very easily ship with an small receiver that can connect to a smartphone or tablet or TV nearby so a person for say Mario Kart multiplayer can use that as a second screen, while the other player can use the NX screen.
