[Pre-Meta-HFTP] Principals for HFTT Proposals, like that for GHC Proposals

GHC Proposals recently got a Principals document. The motivation is explain in the document and the PR, but the basic goal is ensuring the proposals as a whole maintain (or build towards) certain principles.

I think this is a great thing, and the motivation applies equality well to proposal venues of all sorts, including HFTT proposals. So what do you all think of making such a document and incorporating it into the HFTT proposals process too?

One possible example of a principle is:

No unexpected breakage.

The impact of all breaking changes should be known to the upstream projects doing the breaking in advanced to vet the change. Downstream projects goes through should also be warned in advanced with a proper deprecation cycle.

Two examples of projects that implement it:

Being able to witness in the HFTT repo that both initiatives work together can help weave together a larger initiative out of discrete HFTT proposals. It helps confirms a project like warnings on reexports as something worth accelerating with HF resourcing if we decide to do GHC.X.hackage, because the benefit of both projects together is better than that of each alone.