The blurring of the Hour’s character is the consequence of the diminution of daily psalmody and of the new distribution of psalms. The reform at the beginning of the 20th century gave up in great part the 1500-year-old system, as well as the basic principles of distribution. Two generations of priests had grown up without any personal experience of the Roman psalmic order, and, their majority simply did not know about its existence. The Liturgia Horarum – with a more radical resolution – went much further down the path opened 70 years before.
Laszlo Dobszay, The Bugnini-Liturgy and the Reform of the Reform (2003)