Disagree, they rely on both equally, not much more on one of them. Consider the process of actually building a large structure with only a set of such diagrams. The diagrams primarily cover nouns (what, where, using what), whereas the human language formal instructions cover the verbs (how, why, when). You can't build anything with only one of the two.

And sure, the human language formal instructions often appear inside tables or diagrams, that doesn't make them anything less so.

This is based on having worked with companies that do projects in the 10 figure range.