The effect on engines is de to the pulsating nature of the exhaust. Each pulse generates a wave in the duct that pulls the succeeding pulse out, improving scavenging and intake flow. Steady-state flow as in the Dyson fan doesn't get such benefits.Entrained air flow, a small tributary in fluid dynamics. I have seen the concept greatly increase the power in two cycle Schnuerle ported engines. As to this application, I don’t think there is enough duct area to significantly scale up to full size.
Really when you think about it those were pretty violent shows for us tender age little ones. And now we have?? Anyway, gravity didn't really seem to play a part in the physics part of what happens to something when it falls that far or get shot at close range. Unlike airplanes that always are subject to the laws of physics no matter what they are.This investment opportunity exists (and thrives) only in the same physics and logic universe as the cartoons most of us grew up with. Acme Products, Wile E. Coyote surviving a fall of 3000 feet and becoming an accordion, Daffy Duck surviving a shotgun blast to the face, etc.
Which reminds us, once again, that there isn't much in aviation that hasn't been tried already. Spectacular new developments need spectacular new technologies.