Hi! Some new thoughts:
1. Sometimes we (developers) fail to describe system dependencies correctly. Sometimes we just don't know the exact dependency graph. But we feel that something is wrong with A system. Just deleting fasls or touching the source or specific system helps to diagnose this.
2. Sometimes we want to clean system A and then reload system B which depends on A.
3. Am I right that bug with incorrect system definition which loads "successfully" is not fixed yet? Touching the source would help to work around it.
These are just some reasons to extend possible use-case list of clean-op or what whould stand for it.
I am inclined to agree with Andreas. I don't see that CLEAN-OP is impossible for ASDF. I can see that there are some issues that require thought, and for some systems additional coding by the developer, but I don't see that as an insuperable barrier.