Can we do both?

Infrastructure issues considered difficult The largest single problem is that changes to the source document will produce unpredictable and likely unpleasant changes in the remeshed version. Keeping this straight requires a lot more infrastructure, and likely a shift to relative counts.
Portability These documents aren't as easily shared since the information is now spread across multiple files which may need packaging, and which now require an Ool processor. Doing the remesh before shipping is a simple answer, but there may be times when a recipient wants the separated form.
Assumes a single stable source While this approach can reference multiple source documents, it can't keep track of things like multiple possibilities (in translation, for example) in a single source document. It may improve things a bit over standard embedded markup, but not that much.
A bridge of straw As long as you don't put too much stress on it, and meet some strict conditions, this may work for you.