Even then, wouldn't it have been more about case law defining what could be be feasibly prosecuted rather than refining what the law actually says?

If so, it's better, nut still not ideal. It results in information asymmetry for those that don't have a law degree or experience with the system, or can't afford to hire someone who can. That is, law enforcement can use the letter of the law to take actions that aren't enforceable if challenged, but it still requires a challenge be mounted.