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 Nintendo would be stupid to release both components at the same time. To much money for the customer to put out. Releasing both at the time would probably mean many customers only settle for one device.

If the rumor is legit or not, I fully expect for Nintendo to release handheld and home console at least one year separate and handheld first, because they can make more money off the handheld. The home console is more risky for them. I would even expect Nintendo to possibly drop th ehome console, but that is more unlikely.

Buying only one device is all Nintendo needs going by speculation because NX is speculated to be a software platform linking all the devices through one account much like Steam so they wouldn't need people to buy both much like Apple customers don't need to buy both an iPad and iPhone.

I can see them releasing both at the same time during the holiday period, the first set of hardware may not even be the only because under this approach they in theory could release new hardware in smaller cycles because the actual hardware is not the platform.

Exactly. The actual hardware is not the platform. 

There should multiple NXes with multiple form factors. Nintendo cannot support two distinct consoles anyway (a modern portable IS a console for all intents and purposes, the games are not "small" or "easy" to make any longer, they are big budget 3D productions especially once you get above GCN/PS2 level visuals).