To me this seems so much more plausible. The civilization would only need to dedicate a finite amount of time and effort to establishing one or more of these "follies". The signaling structures would live on long after the aliens have either gone or changed their minds. If it were technically possible for us to do it here, I would vote for it.
I would like to say that the Journal of Astrophysics is on my usual reading list, but I was alerted to this revolution in the search for ETI by that refuge of TI, the New Scientist.