Not quite- its from the US 1979 BCP, used by most Episcopalian parishes in the US, a few ACNA parishes, and some of the splinter groups like the Charismatic Episcopal Church. The 1666 BCP (the official prayer book for Church of England Anglicans) does not have this. There are a few other interpolations in the 1979 US BCP that align it more with Orthodox and Catholic practice (the Rite II mea culpa confession, etc), one suspects as a bone to keep the Anglo-Catholics after allowing ordination of women.
This is the kinds of stuff that keeps me here....
My personal BCP was printed in 1976 and says "Proposed" on the title page. The American book has to be approved by two successive general conventions; 1979 was the second convention to do so. 1976 happened also to be the convention that approved ordination of women. I don't know at what stage in the game revisions of the office services were addressed, but it's a cinch it was long before 1976; more likely it was in the 1960s or perhaps even earlier. Besides, most A-Cs do not and did not use the BCP at all, praying instead from one of the various Anglican missals or even RC books.
BTW, the phrase "we are truly sorry and we humbly repent" was added pretty late in the game.
Ah, yes, the missals- harder to find online than the various editions of the BCP. As might be evident from my posts here, my personal exposure to Anglo-Catholicism during my own time with the Episcopal Church was rather limited- the two Dioceses I attended were Central Florida and Chicago, Central FL being largely Low Church (the parish I attended was pretty Low Church indeed) and Chicago... well Chicago was one of the many nails in the coffin of my Episcopalian experience. It's why I refer to my past as being somewhat Broad-High, my personal views were rather high, parish-wise I took whatever I could get.
Most of my information comes from online discussion with the Anglo-Catholics who were left (and yes, I was aware '76 was the year WO was legitimized, part of the reason I'd heard the '79 finalization was the High Church bone. Funny you didn't pick up on my 1666
BCP when it was '62. Stupid dates. I remember discussing the East-West Schism and mis-stating that it happened in 1066- an important date for English Christianity and language, but most decidedly NOT 1054. I'm also bad with names that start with the same consonant, even if the sound is not the same- over the course of Theophany I accidentally referred to it as the Transfiguration multiple times), and given that I was born after both the 76 and 79 conventions I tend to give older Episcopalians a little more weight than Wikipedia.
Wow, that was long and rambling- finals week has devolved me into a barely coherent mess. Anyway, thanks for the further information into the formation of the '79 prayer book and its relation (or lack thereof) to the WO movement.