I think I may have answered your confusion in a different thread (I'm not sure I parsed your comment correctly though), but: this is about a problem that specif

I think I may have answered your confusion in a different thread (I'm not sure I parsed your comment correctly though), but: this is about a problem that specifically occurs when you have JSON (or some other structured format) that needs to have the signature in-band. You're right that it's way easier (the first list of three bullet points, as you mentioned inthe other comment thread) if you can just shiv the tag on the outside. Perhaps a more familiar case where this happens is SAML assertions with inline signatures?