I dug up this interesting post from Fr. John Zuhlsdorf of What Does The Prayer Really Say?
He made a very good analysis of the Book of Blessings, pre- and post-Vatican II. Here is an excerpt taken from his post.
A word about the blessing issue.The new book, De Benedictionibus represents the very worst tendencies of post-Conciliar liturgical ideology and innovation. The forward in the book, explaining its theory – always read forwards! – shows the will of the compilers to destroy the distinction between invocative and constitutive blessings. The former calls God’s blessing down on a person and the later constitutes things, places, etc, as blessed. Those blessings remove things from the temporal sphere and places them in the realm of the sacred. The new book, in eliminating that distinction, eliminates the constitutive blessing. [Just as I pointed out in mymost recent post] If you read the prayers of the Book of Blessings, as the English edition is called, you will find that the prayers don’t really bless anything. They basically suggest that God might bless some who looks at the statue, the bell, the medal, without actually constituting the object as a blessed thing.
This is a grave problem.