Clarify: SCITT tag COSE_Sign1_Tagged is outside the scope of COSE

[SteveLasker]

From @mcr
https://mailarchive.ietf.org/arch/msg/scitt/sOGI7xcUaOJx5Zag8uqsygooLrc/

The SCITT tag COSE_Sign1_Tagged is outside the scope of COSE, and used
to indicate that a signed object is a Signed Statement.

I don't understand this.
"used" is that past-tense, or "is used to"?
If this is not a COSE thing, then where does it come from?

https://www.ietf.org/archive/id/draft-ietf-scitt-architecture-10.html#:~:text=SCITT%20tag%20COSE_Sign1_Tagged%20is%20outside%20the%20scope%20of%20COSE