The thing I love about this is how it brings to mind those invisibility cloaks (against light) that have been in the news in recent years... how it was so difficult to produce the materials for them as you needed to manipulate structures smaller than the wavelength of the light you need to work with (where waves on water have a far longer wavelength), and how it only worked in two dimensions (and, you know... surface waves ). It's the same principle as far as I know... well, I don't have access to the research article through my university and I'm not planning to actually buy it, but it seems like such a simple and beautiful connection.If the scheme works as well in the real world as the lab-scale experiments suggest, a tsunami should be able to pass right by with little or no effect on anything hidden behind the cloak
Regarding Straylight, btw, forget all the talk about tsunamis. The sancts that I like developing are deep-ocean ones. A tsunami in deep water appears as a gentle swaying of maybe a meter or so over several dozen minutes. What you should be afraid of out there is storms and rogue waves... but those are just surface waves too, and this kind of a structure should be able to take care of those quite pleasantly.
* ponders *
... as an unrelated aside, why don't I have any domed surface sancts again?