Not as "spicy" an idea as the Nuclear saltwater rocket however, which instead of discrete bombs involves dissolving a load of bomb-grade fissiles into water and

Not as "spicy" an idea as the Nuclear saltwater rocket however, which instead of discrete bombs involves dissolving a load of bomb-grade fissiles into water and then ejecting them out a conventional rocket engine, with the idea the solution goes critical somewhere in the vincinity of the exhaust nozzle. Now if you're thinking "Does that replace singular discrete nuclear explosions with a continual nuclear explosion shrouded in an expanding cloud of radioactive superheated steam?", the answer is yes, yes it does. Weirdest thing is the design doesn't actually have as much potential ISP as a pulsed detonation system like an Orion, despite being a bonafide torchship. Go figure https://en.m.wikipedia.org/wiki/Nuclear_salt-water_rocket https://en.m.wikipedia.org/wiki/Nuclear_salt-water_rocket