I very much doubt the initial assumption of the OP that sales of Zelda HD would be 3 million on Wii U. That would be pushing it even if the game were Wii U exclusive, but considering if it were also released on NX I think it would struggle to make 2 million. So the NX would have to find 6 million plus. Not impossible, but obviously it would have to really take off and I'm not prepared to make such predictions about the NX.

This.

You doubt many things, remember how that goes for you Mr Dr.Vita? :p

Skyward Sword sold 4 million on a 100+ million install base, compared to Twilight Princess selling 7 million on wii and 1.59 million on GC. Zelda isn't in its prime anymore man, there is no chance of the NX moving units in general without 3rd party support which is highly doubtful at this point. This is way too farfetched.

So besides a Link render and a data mined image is there any proof this thing isn't just a hypothetical game?

SS required an add on and was heavily motion control based, 4m is a brilliant number, TP sold over 7m on Wii with out requiring anything as well as very simple motion controls and coupled with the GC sales hits a total of almost 9m. It's not farfetched that the next game could hit 8m if an NX version is also on the way especially as the U has a strong attach rate for first party games.

What? Pokemon BW on a 155mil install base sold 15.6mil, XY sold 14.1mil on a 55mil install base.

Install base isnt everything and SS situation was quite different than TP, not to mention WW On GCN did 4mil on a tiny install base and its remake is at almost 2mil on the WiiU. 

If Zelda U is a launch game, it'll benefit from it just like most games do.

Not bold, just unrealistic.

That's not the point.  Zelda just isn't as popular as it was with OOT.  Notice how all Pokemon games are on HANDHELDS because Nintendo consoles just aren't all that.

puhahahah no way