I think that's kind of the point...we are passive agents in these sacraments, because God does the acting. All we can do is assent to God's action by saying, "Amen." If the grace depended on proper "vows", per se, it wouldn't be grace at all. I don't mean to turn this into a "faith vs. works" thing; that's not where I'm going at all...but at least in the case of ordination, it is the Holy Spirit that enacts these things in the candidate, and the people assent to it by giving their "amen" and saying, "He is worthy." The ordained candidate says nothing at all; he's simply "led" around the altar and vested; it is just expected that he knows what he's getting into.
In regard to the baptismal vows, we often have a tendency to separate the different parts of the baptismal service - i.e. service of making a catechumen, baptism, chrismation, etc...but really, it's intended to be one continuous action; yes, I understand that the catechumenate and baptism are often separated in the case of adult converts by months or even a year or so, depending on the person, but with infants, it's all one shot, with the end result and goal being full incorporation into the body of Christ. I would assume the article is referring to the vows made during the prayers for making a catechumen, and terming them "baptismal vows."