Do you use the default button layout?

[Ange]

That describes shake smash .

It isn't accurate, and can be too sensitive at times. You could only do a side smash reliably, and I'm not sure if you could charge it.
It feels lie it was shoved in at the last minute, but it could have been a decent alternative to the c-stick if they actually made sure when you moved it down you wouldn't smash to the side.
I wouldn't try it.

If you cant charge it, thats pretty useless. o_o I bet it involves like instant-pressing on the A button or something, my guess.
Off-topicly, it reminds me of all those PAINFUL times Ive played Okami, cause you have to shake the **** remote everytime you would attack. Very painful. q_p

 

[Mama_Luigi!]

I use the wii remote and nunchuk combo (wait, what?!) and I turned tap-jump off, and the D-pad to smash attacks.
(except for the forward smash, because I find it too difficult to do a side taunt by simultaneously pressing 1+2...and the game won't let me put side taunt to anything else..)

 

[Raym]

I use Wiimote+Nunchuk and i use the digital pad for smash attacks.