This is an important explication Henry.
There are a couple of sentences I’d like to comment on:
Working together with User Interface designers, the programmer can build a mapping from any instance graph using the schema to user interface elements, so as to display the relevant data in a way that is easily understandable by humans in a given cultural context.
and
the semantics of such data is mostly determined by humans looking at presentations of them through well designed user interfaces
As McLuhan famously noted, the medium is the message. In other words, “well designed user interfaces” are subjectively meaningful in themselves. They are core to your thesis not separate from it or even meta to it.
The hi:project architecture has interfacial components and methods being subject to their own graphs, the user’s contextual selection and interpretation, and continual adaptation in finding one’s truth.
It’s been a few years since we had a good chinwag on the topic, so just wanted to resituate the project in your current context :-)