I guess the only bit I don't really agree with is this: > upfront investment in thinking about the correct types being a cost. Surely you have to do this wh

I guess the only bit I don't really agree with is this: > upfront investment in thinking about the correct types being a cost. Surely you have to do this whether the compiler will check your work or not, and if you just don't do the thinking you'll end up with bugs? Isn't this a benefit?