Actually, though, we already recognized the validity of the baptisms of anyone who baptizes in the name of the Trinity.
Catholics still consider baptism a holy sacrament, right? If that's still the case, then you would consider our baptisms to be invalid. That's what you told me before, re the validity of Presbyterian sacraments...
Well, Alex, since, e.g., Prebyterians reject apostolic succession, reject the idea of the priesthood per se, and reject transubstantiation or anything close to it, there's really not much chance of a Presbyterian Eucharist being a valid Catholic sacrament. Sacramental validity requires a valid minister, valid matter ..., valid "form" (the words that are said, and valid intent (the intent to do what the Catholic church does). Unless your Presbyterian minister is a former Catholic or Orthodox (or perhaps Anglican) priest, he's not a validly ordained minister. He probably doesn't have a valid intent, either.