Oh, I didn't mean that Sidious was involved. I'm sure it's exactly like you say.
I just meant that I suspect that Maul got some ideas from working for Sidious on how to pull it off, because it's such a similar idea to what Sidious was up to.
On the other hand, I suppose they both could have both learned the craft from Sith masters of lore. Maybe that sort of double-dealing is the sort of thing that the Sith have always been up to.
I'm probably reading too much into it anyway.