Here is some of the historical rationale they provide for why this comeback should be a sign of health:
[T]hroughout the two millennia of Christian history, the health of Christian communities has, in fact, often been linked to the presence or absence of serious catechetical ministries.Besides exploring the biblical and historical rationale for the practice of catechesis, Packer and Parrett provide helpful and practical counsel on how to actually go about doing it in the church today. This is a book well worth reading...and applying. It would do a world of good for our churches, their members, and the effectiveness of our witness to the truth of the gospel.
It could well be argued that the Reformation itself was a response to centuries of catechetical decline.
And quoting Calvin: Believe me...the Church of God will never be preserved without catechesis.
Of course, it should also be noted (especially on this blog) that there are a number of original hymn texts written by Parrett in the back of this book.