Not an expert but I'm pretty sure that constitution > statutes and ordinances > rules and regulations. Meaning that USCIS must follow the intent of the law when publishing regulations. In the case of H1B the law is clear that it gives a specific status of temporary worker distinct to the immigrant status. USCIS itself acknowledges it:
https://www.uscis.gov/newsroom/news-releases/us-citizenship-...
> Our system is designed for them to leave when their visit is over. Their visit should not function as the first step in the Green Card process.