The poster you're replying to said "just take the lower half of the cohort in each categorty (mental/physical) in a given study and give them intensive one-on-one training in all areas for a year". Pretty much every study has show that one-to-one tutoring is far, far more effective than the standard "education" system.
>We collectively have enormous amount of experience in educational interventions, and, in short, none of it really works.
What are you talking about? There's plenty of evidence that one-to-one tutoring can be quite effective at increasing test scores. Yes this approach can't be deployed at scale due to the sheer cost of it, but that's completely irrelevant to the question of whether intelligence is trainable.
You should watch some https://en.wikipedia.org/wiki/Memory_sport competitions, would blow your mind what people are capable of training themselves to do.
> You should watch some https://en.wikipedia.org/wiki/Memory_sport competitions, would blow your mind what people are capable of training themselves to do.
What some people are capable of, yes. Does it translate to those people being better at other mental tasks of mental ability? No.
Two sigma https://en.wikipedia.org/wiki/Bloom%27s_2_sigma_problem is not a "marginal" effect. And a chunk of that can be explained by mastery learning, which while still hard to scale up is far easier than individual tutoring as a whole. The educational system is not institutionally incented to effectively pursue these empirically workable approaches. It's a matter of bureaucracy-driven failure, not some immutable fact about the world.
There's even specifically developed approaches to effectively train and educate those who might be often described as 'low I.Q. individuals', such as "direct instruction". Guess what, they get no takeup from the educational establishment, simply because they're (quite wrongly!) perceived as being demeaning for teachers.
The average teacher would rather pretend to educate those who are already highly functionally literate and familiar with educational dynamics (including test taking, of course) and can simply "learn by themselves". Education schools consistently cater to these attitudes and push the same approach.
Consider learning how to throw a ball. Do some new students 'just get it' - or did their parents spend hours tossing a ball with them previously? Point being, those anecdotes about students who just get it don't factor in variables like earlier childhood education etc. Few people would argue that such physical skills are not eminently trainable - and clearly, mental skills are also trainable.
The question is, is there something like a clearly delineated genetic factor than makes it easier for someone to, for example, learn a new language, relative to someone lacking that factor? No real clear evidence seems to exist for that claim.
Anyone who has actual and nontrivial experience in teaching (say, over 50 students over at least few months) will tell you this simple empirical fact: some people just “get it” much easier and quicker than others. The only way to escape this reality is to sort people by mental ability, so that you only see people in the same ability bracket, but that’s just it, an escape.
We collectively have enormous amount of experience in educational interventions, and, in short, none of it really works. It’s easy to complain about lack of resources, about low teacher quality, about wrong methods, and all of these are in fact real problems, and pretty complex and hard to tackle too. At the same time, even if we pull each of those to the state of the art, we can only expect a marginal improvement.
Have you noticed how the educational establishments seem to try a new thing every 5-10 years or so? That’s because none of it really pushes the needle, and these 5-10 years are what it takes to realize that. In reality, the “new thing” is in fact usually an old thing that has already been tried a generation or two ago, but which has not been seen by the current generation of education workers. That’s because everything has already been tried, and none of it really works.
On a more optimistic side, that means that even if the education system is suboptimal, it doesn’t really matter, as outcomes are more or less the same anyway.