The ability to produce lots of children does not at all work against the ability of innovators and innovator probability to overcome their resource-extraction load.
I'm not following your terms here. Obviously the ability to produce lots of children does in fact sop up all the additional production, because that's why per capita incomes on net essentially do not change over thousands of years and instead populations may get bigger. So you can't mean that, but I don't know what you mean.
China and India (and the Islamic Empire) did innovate faster than the West, and averted many Malthusian overtakings along the way (probably reaching 800 years ahead at their zenith). Malthus would have known about this at the time.
They innovated faster at some points, arguably. And the innovation such as in farming techniques helped support a higher population - and a poorer population. Malthus would have known this about China, did, and used China as an example of a number of things, for example, the consequences of a subsistence wage which is close to starvation http://en.wikisource.org/wiki/An_Essay_on_the_Principle_of_Population/Chapter_VII :
The only true criterion of a real and permanent increase in the population of any country is the increase of the means of subsistence. But even, this criterion is subject to some slight variations which are, however, completely open to our view and observations. In some countries population appears to have been forced, that is, the people have been habituated by degrees to live almost upon the smallest possible quantity of food. There must have been periods in such counties when population increased permanently, without an increase in the means of subsistence. China seems to answer to this description. If the accounts we have of it are to be trusted, the lower classes of people are in the habit of living almost upon the smallest possible quantity of food and are glad to get any putrid offals that European labourers would rather starve than eat. The law in China which permits parents to expose their children has tended principally thus to force the population. A nation in this state must necessarily be subject to famines. Where a country is so populous in proportion to the means of subsistence that the average produce of it is but barely sufficient to support the lives of the inhabitants, any deficiency from the badness of seasons must be fatal.
In an erratum to my previous post on Pascalian wagers, it has been plausibly argued to me that all the roads to nuclear weapons, including plutonium production from U-238, may have bottlenecked through the presence of significant amounts of Earthly U235 (apparently even the giant heap of unrefined uranium bricks in Chicago Pile 1 was, functionally, empty space with a scattering of U235 dust). If this is the case then Fermi's estimate of a "ten percent" probability of nuclear weapons may have actually been justifiable because nuclear weapons were almost impossible (at least without particle accelerators) - though it's not totally clear to me why "10%" instead of "2%" or "50%" but then I'm not Fermi.
We're all familiar with examples of correct scientific skepticism, such as about Uri Geller and hydrino theory. We also know many famous examples of scientists just completely making up their pessimism, for example about the impossibility of human heavier-than-air flight. Before this occasion I could only think offhand of one other famous example of erroneous scientific pessimism that was not in defiance of the default extrapolation of existing models, namely Lord Kelvin's careful estimate from multiple sources that the Sun was around sixty million years of age. This was wrong, but because of new physics - though you could make a case that new physics might well be expected in this case - and there was some degree of contrary evidence from geology, as I understand it - and that's not exactly the same as technological skepticism - but still. Where there are sort of two, there may be more. Can anyone name a third example of erroneous scientific pessimism whose error was, to the same degree, not something a smarter scientist could've seen coming?
I ask this with some degree of trepidation, since by most standards of reasoning essentially anything is "justifiable" if you try hard enough to find excuses and then not question them further, so I'll phrase it more carefully this way: I am looking for a case of erroneous scientific pessimism, preferably about technological impossibility or extreme difficulty, where it seems clear that the inverse case for possibility would've been weaker if carried out strictly with contemporary knowledge, after exploring points and counterpoints. (So that relaxed standards for "justifiability" will just produce even more justifiable cases for the technological possibility.) We probably should also not accept as "erroneous" any prediction of technological impossibility where it required more than, say, seventy years to get the technology.