Masai people must be super clever and Finnish people too. It must be true because I know a lot of really clever Dutch people and they are all really tall! Chinese people must be really stupid. I am so glad you gave me this insight. I am tall and I feel great now.
He/she is quoting "these average race differences in brain-size/IQ relations were not due to body size", i.e. it is an average within a population group rather than amongst population groups so you appear to be making and attacking a straw man argument.
