But why do you find it so hard to believe that the Wii U would be able to handle PS4/720 multiplats? Will it run it just as good? No but it's very possible it will be able to handle the games unlike the Wii.
Nothing is impossible, obviously.
But if some of the next Xbox and Playstation's specs are to be believed it's like expecting the big blockbuster current gen titles (Red Dead Redemption, GTA, Halo, Bioshock, Assassin's Creed, Crysis, etcetera) to come to the Wii.
They didn't, even though it could have been technically achievable.