The 15-20% drop only accounts for the competition from mobile, and represents a best-case scenario. It assumes everything from release scheduling to marketing is rock-solid. Something I don't have confidence that Nintendo can pull off, given their recent history. The 50% is far more representative of what I would expect to actually happen.

They should be able to get the scheduling part of it right, without resources having to be split into two platforms and being able to focus all energy on basically one platform ... they could have a really stacked release schedule. 

I have doubted Nintendo before and every time, I'm proven wrong. I'm not doubting them again. I think after all these years, they've earned the benefit of doubt imo.

I think they'll come back with some piece of hardware that will compel gamers enough to buy it.

It should also help them with marketing/advertising by not having to sell two seperate product lines and as long as they dont have goofy names or gimmicks that are hard to demonstrate then they shouldn't have nearly as much customer confusion.

It might be possible, but we don't even know for sure if the Nintendo Fusion is a thing!

I'm fine with gimmicks as long as they dont significantly increase the price of the hardware and if they are expensive than make them optional.

I think the next handheld will be to Wii U as 3DS is to Wii, a somewhat weaker device but using more modern components that can produce Wii U level visuals at a lower resolution. The console will then be to Wii U as Wii is to Gamecube, a more beefed up version that plays the same games as the handheld at a higher resolution with some extra graphical effects.

Nintendo will have a handheld and a console next gen like every gen, they aren't going to do a "fusion" type console.

Nintendo can still have a powerful HW and still have some controller magic trick up their sleeve, without a hefty price tag on both consoles.
It will most likely depend on component parts and their software output.

Even if the Fusion strategy is, in terms of HW, a money losing one, the increased profits in SW sales, less money used in activities like marketing, NEW Amiibo figures (a new line of Amiibo!), might offset the losses at first and even make a profit.

But in the end, what good would a powerful Wii 3 do?
As we have seen over and over again, it was not powerful HW that made Sony a success. Even PS4, who is winning, is doing so because the only competition gamers care about completely failed in there eyes and Sony excelled.
PS4 isn't that much powerfull than the XB1 to be winning by such a wide margin.

More than having a powerful HW, Nintendo needs, unlike what it did with the Wii U, it needs games, right from the start, that showcase what the systems are all about.
Wii U completely failed at that: it's biggest showcases were a new 2D Mario game that looked like its Wii brother in slightly better graphics and NintendoLand. That was it.
Also, you need to show your big guns, just like Nintendo did in 2006. That was a lesson that somehow Nintendo forgot or just wasn't ready to show anything else because it didn't have anything else.

And this why Fusion is so important and vital to Nintendo.

Nintendo is no longer in a position where it can choose what type of strategy is best for them.
They are out of options!
Wii U has been nothing but a mess in terms of game development: lack of games in the first half for 3 years.

They no longer can support a home console. 3rd parties are no longer there ofr them.
The handheld market is thir best because it's old tech and japanese 3rd parties have their back. But at the same time, its market is being eaten by mobile gaming.
Going into next gen, can they really afford to keep supporting their consoles all by themselves, especially their home console?

It's no longer of choosing between visions of what path they should follow, it's a matter of how can survive in
the market.
Things have reached a point that not even great games of their best franchises can breathe a new life into their home console market. Why would anything change next gen if Nintendo keeps the same strategy?

" Prediction: the NX will sell 80m+"
Fixed. :D