Glued assembly parts as closed solids

[Philippe Hurbain]

In relation to assembly parts (see Ostrich), should all the component parts be closed solids? While I'm sure there are examples of both in the library, Chris's standard seems to have been closed solid:
https://library.ldraw.org/tracker/24369

I agree but I'd like to have a short discussion in case anyone has strong feelings against.

No strong feeling but I think that removing a constraint in parts authoring would be a good thing... Anyway, most parts are not closed solid strictly speaking, and so many internal parts closures are purely artificial and bear little or no similarity with reality!