To say that "post-modern science is in practice a return to medieval science" - wow. It is the first time I encountered that point of view. In the research community where I work, where collaboration between South African, Canadian, Finnish, British, Dutch universities and several universities from South East Asia continually takes place, I have never heard of such a claim. Please explain your point so that I may discuss it with colleagues.
Your critic against peer-review, supported by the quote by Dr. T Gold, is valid and that is why peer-review is just one of several modern academic mechanisms used to test the academic authority of research. (the practices you listed under the term "peer-reviewed" are anyway suspect and far removed from the reality - if a peer-review happened in the way you described, no promotor or editorial board of any respectable accredited journal would accept the validity of the process)
Modern education theory has developed light-years beyond the theories of Dewey, Piaget and their peers way back then - the old behaviouristic theory of education from that time, by the way, was the "scientific basis" for the impuls-response approach to conditioning (does that sound familiar...? "*if* my son whines/.../.... then
I just whack him a few shots because the result
of the spaking made him stop - see, it works!")
But back to modern international educational theory. It is much more interpretivistic than before, less simplistic, and much more pragmatic - by interpretivism we mean "a scientific approach which strives for understanding a phenomenon rather than simply describing it" and by pragmatism we mean "of useful value for the practice; of practical use". Also, modern educational theory employs the so-called "critical theory" approach which seek to re-examine "accepted truths from classical or traditional scientifoc theory".
You also quote "a story you heard" about a teacher in the 1930's who...
I could point out that this type of "evidence" is purely anecdotal - but, out of respect for your sincerity and honesty I shall not discount it and attempt to respond just as honestly:
Firstly, a situation where a parent or teacher needs physical violence or physical intimidation to subdue a child or student does not in any way
fit in with modern education theory - it is an example of primitive behaviour similar to what you would expect from animals like primates; if you really stretch it you could maybe recognize in such an approach to "discipline" elements of the old behaviourist model of conditioned behaviour which I referred to in a previous paragraph.
Secondly, I would like to extend the argument that this anecdote seems to make: If you "discipline" young people by brute physical violence and in doing so, what is the nature of the values you are instilling in them? Something like, "respect and subdue yourself only to abusive authority, because they can hurt you?" - sounds to me like the very basis of a police state, don't you think?
The explanation for the better performance of pupils in private schools may be ascribed to many well-documented factors like expert teachers (who receive better pay because they have academic credentials which distinguish them), stronger pupils (these private schools often apply more stringent admission criteria), smaller classes, better educational technology and media, a better motivation and competition among pupils, better socio-economic background... Because of these factors, there will probably be little need for instilling any other form of discipline but self-discipline. The nature of such schools and their pupils are very different from what you find in the case of public schools. I see no basis for believing that the application of disciplinary measures is a primary factor which explains the better performance of these schools.
My point remains that modern educational practices should be informed by scientific and legal considerations, not by tradition, religion, anecdote or other suspect beliefs.
Again: make a quick study of first-world countries where all forms of corporal punishment have been abolished and look for examples of unstable societies, examples of countries notorious for household violence, examples of countries known for mass-killings, examples of countries where youth crime are on the rise, examples of countries on the verge of social collapse.
Instead, I daresay, you will find examples of some of the most peaceful, prosperous and stable countries in the world.