I am sceptical too, don't worry
I still have to read the whole article on that one though.
Darwin's theory has had some following up till the '80s, as it was pretty much the only theory until then. In 1984 the giant impact theory became the mainstream one, I believe.
Your argument about the detachment is true, but the Moon detaching is a bit strange and not very likely. I still don't really know which theory I find the most likely, I still need some more info on the composition of the Moon and the theories themselves.