For me it would be a chance to learn the under-structure of a course as it is being built. The nuts and bolts that without which the top simply wouldn't work.
In other words, the why's and how's of drainage. The types of materials that go underneath to promote healthy turf. An understanding of why an undulation is simply that while many other times it is a necessity that allows the overall drainage to work.
How routing a course also involves the intertwining, not only of what is seen but what is not; those same underpinnings that allow for an entire area, not just a green site for example, but say several holes, fairways and all, to drain water in ways that will not unexpectedly prevent water from draining elsewhere.
Water is both life and death to a golf course and in ways that few of us, including myself, simply don't understand.