> The “obvious” answer, if my above assertions are true, is that it must not actually represent a thermonuclear secondary. [...] It could be some kind of pre-approved “unclassified shape” which is used for diagnostics and model verification, for example. There are other examples of this kind of thing that the labs have used over time. That is entirely a possibility.

However, he then goes on to immediately reject this "obvious" answer, because he thinks the well-known schematics of fission-fusion bombs give the appearance of a classified shape, and because he feels it is "provocative" for a government weapons lab to show a mock up of a well-known schematic in one of their publications. Those positions seem very weak to me.