I like to point out that when Literate Programming was first proposed, software was a great deal less malleable than it is now. LP vs. the rigid structures of the time is one thing, LP vs. the malleable structures of today is quite another. Cast back in time I might prefer LP in the past, but today, it's an awful lot of complexity and a huge layer to add on top of our systems for what is of significantly less relative utility. Very little stops you from having more narratively-coherent code today, in existing systems; the problem is more human than tool now.