Your example is the oversimplification that causes people to disbelieve CICO. In your example the body adjusted and the CO wasn't stable. CICO still holds, the flaw is the person assuming their CO was stable.

People who staunchly support CICO as the end all be all talking point miss what you describe. At the same time people who decry CICO as being bogus are missing what I describe. Both are true and both are wrong. It's really just a semantic argument.