Replying to my own message: The proposed text would then read: This specification defines a protocol, Simple Certificate Enrolment Protocol (SCEP), for certificate management and certificate and CRL queries. While widely deployed (see the <xref target="background">Background Notes</xref> section for more on the history behind SCEP and the nearly two decade-long progress of this standard), this protocol ... which I think explains the nature of the "widely-deployed" comment while not overloading things with a huge load of historical commentary. Peter.