So the Mass in this revised BCP is essentially "the Liturgy of St. Tikhon"?
What about the other daily services, like Matins (published in a separate volume), Compline, and the Hours? Do they reflect the ancient (pre-schism) usage, recent Anglican usage, or have Eastern elements been introduced to Orthodoxify them?
This is something I keep coming back to. Proponents of WCR claim that sufficiently complete liturgies and rubrics exist from the period prior to 1054 to be able to establish a living link with them. I do not believe that can be substantiated. Source materials are too scarce and too incomplete to know what was normative anywhere in the West. To take something as simple as the music to which the liturgy would be sung, no one knows anything for sure about its rhythm, and the relative pitches of its melodies is strictly conjectural before about 1200. The meaning of some of the notation is still subject to hot disputes to this day. Further, the three earliest primary sources for the Sarum Rite are all post schism. Of course, it is likely the pre-schism practice was similar, or even identical. But we really don't know for sure. The liturgy engaged the efforts of the best artists of the day--musicians and poets. It was definitely subject to "fashion," which usually brings rapid change.
One speaks here of a "Roman Rite." Since we live in a time where Rome dictates nearly everything for the Catholic church, we imagine we know what that means. But even post-Tridentine liturgies in the West showed quite a bit of local variation, despite claims of universality. The (Tridentine) Roman Rite wasn't adopted for the archdiocese of Paris, for example, until the middle of the 19th century. So now go back 800 years and imagine how much more chaotic a Western Europe mired in the Dark Ages would have been, Viking attacks, no stable governments, constant warfare, near universal illiteracy...