No. He was a poor comedic relief character that Lucas thought was funny and then wrote out when no one liked him. Fan give him way too much credit in this theory.

Whether this was true or not, the Expanded Universe was completely retconned, so now almost nothing from before the Disney's buyout is canon anymore. So no.

The fact that he's mouthing the words Amadala says kind of makes this believable for me.

There's no logical explanation for it, if Jar Jar is not manipulating them. It's not like an actor who could have just messed up. They had to specifically go out of their way to animate this.

Jar-Jar secretly being a Sith Lord makes the prequel trilogy more enjoyable, so I'll buy in to the theory until Disney provides a definitive answer.

As for his goals, they could have simply been to act as a political plant, guiding the opinion of the senate whenever Darth Sidious couldn't, or would be overplaying his hand in doing so, or simply needed more votes for things to go the way he wanted.

This is cool, good film theory and it makes sense.

Imagine a scene where he drops his silly acent, and that way he talks like a idiot and suddenly hes talking normally but like really menaceing.

He whips out a red light sabre and starts hacking at jedi, who just stare at him in disbelief. Not believeing that evil had walked beside them without them noticeing it.

He's heard in the original trilogy. I'll never buy Jar Jar more than anything, but a moron.

He was intended to be but LucasArts have (regrettably) given up on that concept. I doubt they will make it happen in the one rogue saga.

^ this.

Last minuet changes, ment Jar Jar never became what he was supposed to be.

A wolf in sheeps clothing. I really like this theory, shame they didnt do it or stick with it.

I think he was a very bad idea from a man that has no idea of what made him successful