The search for extra-terrestrial life

In his paper "Transit Lightcurve Signatures of Artificial Objects" (Journal of Astrophysics) Luc Arnold proposes that aliens would not bother blasting enormous amounts of radiation into space in the hope of contacting someone (as SETI hope), but rather they would occlude a suitable star with enormous orbiting objects. A suitable arrangement of "dots-and-dashes" could spell out some signature of intelligence: a handful of prime numbers, or the first few digits of PI perhaps.

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.