I did not know about the switch-based co-routines, but they made me groan and giggle at the same time. I try to come up with a real-world metaphor to describe

I did not know about the switch-based co-routines, but they made me groan and giggle at the same time. I try to come up with a real-world metaphor to describe this mixture of horror and delight to non-programmers, but I am not sure there is one.