That is classic! I love it, but what came up next was unreal. I’ve never seen the video of demon carb doing that.
What I do know is I had a Holley carb that did the exact same thing. I never fixed it, and no one else would (or could) either. When I called with the list number every carb guy in the country said just get a new carb. That happened to be an annular discharge. That damn thing had an 850 venturi and 1.688 throttle blade, which is *** backwards. It had a giant hole in the fuel curve just like that.
That carb was bought by my brother back in 1988ish and was used on several different combinations and it was always the same. I could never figure it out and never found anyone who was willing to try and fix it.