Probably, but Brazzy's explanation without adding all those other variables fits well enough to show why Milton's statement might have been missing something important. The point of a jobs program is that society pays some cost (of not using the most optimal method, i.e. more machines and fewer workers) in order to keep its members out of the unemployment trap. To propose, even as a deliberate reductio ad absurdum, that this would go just as well with spoons rather than shovels is not rationality, it's Spock-logic.

Now I'm quite willing to suppose that he understood the usefulness of such programs as an economist and overall had good reasons to see them as not worth it, or that some other measure would do better, but that particular quote fails to show it.