Excuses mc scusses.
Just give us the best dang game possible.
Quite frankly, the SSE took up over 3/5th's of development time (Sakurai's words, not mine), and I would have rather seen that gone to other places, namely the character balance, the roster size (Roy and Mewtwo would have been nice), having Melee's old adventure mode back (and bigger than ever), more stages, and more content users can customize.
On top of that in Brawl, the SSE combined with the music took up over 6 gigs of the 7 1/2 or so on the disc, requiring the disc to be dual layered. With the 3DS, that's problematic, because the 3DS cartridge limit is 8gb, and there have been no 3DS cartridge bigger than 4 gb made (it also means Smash 3DS will have less music, and probably less stages).
Because the Backroom has a hotline to Sakurai... Clearly...
To be fair, one of the BRoomers members (I'm a part of it, but not the leader, although I do lead in posts in the Broom)
did have a leaker pre-Brawl (but he only got the basic characters confirmed post-all the rumors being all but proven true, and a few stages [namely 75m before anyone else found it in the game]).
Other than that, we got nothing for Smash Wii U and 3DS, other than said person's former sources tell us that they aren't in the know, but that E3 rumor (with Pac-Man, Miis, and Little Mac) definitely sounds legit.