I read it too and found it to be intriguing, and all the more convincing since it was written by paedobaptists and concluding that infant baptism was NOT the practice of the earliest churches. I wish they went on to explain why they happened to remain paedobaptist by conviction.
during the early period you describe, would it have been realistic to have stern anti-paedobaptists
I agree with Tim's basic perspective here. The early church fathers are often a garbled and thus ultimately an unreliable source by which to try and gauge apostolic/biblical belief and practice. The most that can objectively be said about Tertullian's writings on this subject is that they contain the earliest definitive (universally acknowledged) reference to infant baptism (c.202 AD).
But now, covenant theology has provided a defense of infant baptism.
It is significant that he was a lone voice amidst many and yet denounced by the church or apologists for his views. This shows, again, that the church probably did not speak with one voice on this issue, as they had regarding the eucharist. ... but, I'm still left with the assumption, which I think is still a strong one, that earlier Christian communities would have been more privy to the teaching and practices handed down by the apostles themselves, no?