WAIT A MINUTE.
Treehouse people said they have had access to newer builds at E3. But they never explicitly said all of the characters... What if a treehouse rep is sal's leaker. Crazy I know, but here me out, it lines up.
If not a treehouse person, at least somehow involved near that area. It lines up 100%.
- Treehouse gets builds every few months as said at E3, Sal leaked two different sets of characters... from different build maybe?
- Treehouse people have some word in game development, they would know if Lucas was being debated
- It's not too much of a stretch to assume that they tell Treehouse reps just a little in advance about the videos and announcements
- They still have not received the final build of the game yet obviously, which would include secret characters. SO of course he would not know the rest.
- This also explains why Sal's leaker hasn't given any context of who else is playable. IF he said he tried an early demo, then Nintendo would know exactly where those demos are... at the Treehouse!
- I'm not saying it's one of those people at E3. I am saying that the most likely scenario at this point is that someone who at least works in that building is Sal's Leaker.
- One of the BIGGEST reasons for this entire theory is how they knew about 5 characters at E3 LAST YEAR. They likely got a very early build and were just told some of these characters would be revealed at E3 2013. Sal's leaker then just takes all those characters, and sends them to Sal. BOOM.
This is an insane Theory that may be way out there, but after Sal's leaker knowing Shulk will be revealed tommorow, it just all fits together like puzzle pieces.