Except that if the theory is (as I believe), correct, then his entire act in Episode one was a series of obfuscations and subtle manipulations. And why would it require a flashback sequence?
Because if you don't put some foreshadowing in, things are gonna look stupid. You're implying an arc as big as Anakin Skywalker's arc, or some parallel to it--we all know how much young Anakin in TPM was loved, and then his older self later on with that deep angst, all the while the audience knows that, "this is Darth Vader". No way in hell is this going to work, unless The Phantom Menace ends up a misstep and Attack of the Clones and Revenge of the Sith are two god-tier movies.
Seriously, I thought the "Darth Jar Jar" thing was a meme. Was Jar Jar's role in II and III reduced (nearly cut for Episode III) and rewritten after his character flopped, definitely. Was he supposed to be one of the great Sith Lords driving the plot as "Darth Jar Jar"? Yeah no.
You might've written Jar Jar a bit better, added the foreshadowing and vague flashbacks to show he's not just some alien buffoon, and that would've laid the groundwork storywise for this Darth Jar Jar. Since Lucas did not in TPM, clearly if Darth Jar Jar was intended to be real at all, he would've flopped hard with the audience. The fact I'm arguing this point shows that to successfully execute this idea in a way the audience is not cringing at would've needed so much caution and subtlety which we know that Lucas is not capable of.