My argument is that spanreeds are much more complicated. It is possible that the mechanism that allows them to be switched on-off cannot be replicated on a larger scale.
But spanreeds are very, very different from these. You can send signals through them(flashing), I think that we cannot instantly apply what we know about spanreeds here.
I don't get why there is a problem. Your dice analogy in my opinion was exactly correct. They need to use aluminium because otherwise when they would rotate the chull latice, the airship would also rotate.