1. You are right that we can redefine what is code. If code is the central artefact that humans are dealing with to tell machines and other humans how the system works, then CodeSpeak specs will become code, and CodeSpeak will be a compiler. This is why I often refer to CodeSpeak as a next-level programming language.
2. I don't think being deterministic per se is what matters. Being predictable certainly does. Human engineers are not deterministic yet people pay them a lot of money and use their work all the time.
Human carpenters are not deterministic yet they won't use a machine saw that goes off line even 1% of the time. The whole history of tools, including software, is one of trying to make the thing do more precisely what is intended, whether the intent is right or not.
Can you imagine some machine tool maker making something faulty and then saying, "Well hey, humans aren't deterministic."
* regression tests – can be generated
* conformance tests – often can be generated
* acceptance tests – are another form of specification and should come from humans.
Human intent can be expressed as
* documents (specs, etc)
* review comments, etc
* tests with clear yes/no feedback (data for automated tests, or just manual testing)
And this is basically all that matters, see more here: https://www.linkedin.com/posts/abreslav_so-what-would-you-sa...