A study on changing attitudes towards educational methodology, especially in the department of English, will explain the parallel changes in Bible translation. The days of stiff scientific philology gave us the RV. Later the tendency towards technical terms, stylised sentences, and purpose-built English led to the RSV. Then the movement towards self-expression and lack of grammatical and syntactical form has produced translations like the GNB and NIV.
Matthew, that observation reminded me of a fascinating essay from Theodore Dalrymple, "The Gift of Language" in Not with a Bang but a Whimper: The Politics and Culture of Decline. I no longer have the entire article to hand, but it addresses itself to the question of changing educational standards for English and their impact on wider society, as can be seen in the following excerpt:
With a very limited vocabulary, it is impossible to make, or at least to express, important distinctions and to examine any question with conceptual care. My patients often had no words to describe what they were feeling, except in the crudest possible way, with expostulations, exclamations, and physical displays of emotion. Often, by guesswork and my experience of other patients, I could put things into words for them, words that they grasped at eagerly. Everything was on the tip of their tongue, rarely or never reaching the stage of expression out loud. They struggled even to describe in a consecutive and logical fashion what had happened to them, at least without a great deal of prompting. Complex narrative and most abstractions were closed to them.
In their dealings with authority, they were at a huge disadvantage—a disaster, since so many of them depended upon various public bureaucracies for so many of their needs, from their housing and health care to their income and the education of their children. I would find myself dealing on their behalf with those bureaucracies, which were often simultaneously bullying and incompetent; and what officialdom had claimed for months or even years to be impossible suddenly, on my intervention, became possible within a week. Of course it was not my mastery of language along that produced this result; rather my mastery of language signaled my capacity to make serious trouble for the bureaucrats if they did not do as I asked. I do not think it is a coincidence that the offices of all those bureaucracies were increasingly installing security barriers against the physical attacks on the staff by enraged but inarticulate dependents.
(...)
Beginning in the 1950s, Basil Bernstein, a London University researcher, demonstrated the difference between the speech of middle- and working-class children, controlling for whatever it is that IQ measures. Working-class speech, tethered closely to the here and now, lacked the very aspects of standard English needed to express abstract or general ideas and to place personal experience in temporal or any other perspective. Thus, unless Pinker's despised schoolmarms were to take the working-class children in hand and deliberately teach them another speech code, they were doomed to remain where they were, at the bottom of a society that was itself much the poorer for not taking full advantage of their abilities, and that indeed would pay a steep penalty for not doing so. An intelligent man who can make no constructive use of his intelligence is likely to make a destructive, and self-destructive, use of it.