[lemmsjid]

Hmm, not really, I was more giving the GP the benefit of the doubt that they have some, so maybe they'll chime in. I think they were focusing on the fact that idempotent systems often need to interact with other systems that are not idempotent, but then the act of dealing with those systems, the surface area, can often be made idempotent. To raise the stakes very high, I picture software operating a military robot, where it is quite important that it fire its gun only the specific number of times it is cleared to by external logic. Instead of attempting to guarantee that the robot is sent a 'fire gun' message only the requisite number of times, the system should focus on putting the robot into a 'fire gun' state, the messages of which that sent the robot into that state can be made idempotent...

I certainly support your toying, because I think a lot of impedance to idempotency is the lack of easy patterns to achieving it.