People have spent enormous amounts of time and effort to find clever optimizers. This is another example of that. I don't really see this as any less clever than if someone had written the algorithm by hand.
And you can invent this by hand. I was talking to Shawn Presser literally days before about his experiments in cutting down Adam to low-precision, where he had repeatedly cut it down, eventually to 1-bit, and found it was still working on small-scale Transformers - ie. close to this LION. (He didn't invent it exactly, but was like an `abs()` away or something: https://twitter.com/theshawwn/status/1625681629074137088 ) So that's how you could have invented this yourself: follow the logic of '1-bit Adam' https://arxiv.org/abs/2102.02888#microsoft to see how much you can dispense with modeling the moments.
Go use my public tool https://doxyjs.com and find yourself a compression algo; you probably can. If you understand why it works, that's interesting.
It seems like a pretty big leap to assume the authors don't understand their own algorithm.
At the same time… trying to grok-everything consistently kills my attempts at anything business-like, where one has no choice but to focus and delegate.