Minor changes here, but some sound awfully familiar. As I recall, back in the late 1960s and early 70s, we used to say Lord I am not worthy to receive you under my roof." Sounds like they are going back to that. Also, was it not customary in past decades to say "I have sinned through my fault, through my most grievous fault" before they shortened that? This sound almost like they are going back to some old ways when it comes to some of these responses.
Vatican II changes emphasized translations to the local vernacular but those translations homogenized the texts.
I do not recall the under my roof phrase, but I do remember beating my breast three times while saying "mea culpa, mea culpa, mea maxima culpa," and wondering why they reduced it to one 'through my fault'. I also remember wondering what happened to the spirit when they translated 'Et Cum Spititu Tuo' to 'and also with you'.
I'm glad they're finally getting it right.
Bingo. I think you are remembering the Missal of 1965, which was English but more traditional than the Missal of 1970 or whenever it was.
Those are responses that never actually changed in the official Latin text of the Missal. The changes you're thinking of were almost all the result of the original ICEL "translation" (more like "paraphrase" in many spots) of the Latin text.
What this translation is doing is actually trying to translate the Latin accurately into English ... for a change.
I have sinned through my fault, through my most grievous fault"
I remember: through my fault, through my fault, through my most grievous fault"