I think that's only true to a limited extent -- but it's a very interesting point.
The blind spot of most philosophers in this regard -- compared to for example linguists, or grammarians, clinical psychologists, literature guys, spiritual leaders, etc -- is precisely that they are rationalists ; which subsumes the assumption that thought, and therefore only performative language, constitutes the entirety of what could be termed as "understanding". It is an assumption that only the Nominalist, or positive-materialist, position can be considered as valid.
But this is not only to dismiss Perception itself, by attempting to diminish it into a mere "function" of rational cognition, in direct contradiction to its primary function as the source of all direct learning -- but it also diminishes the actual scope and versatility of language itself, which is no means limited by the assumptions belonging to any particular schools of philosophical thought.
If anything, I'd suggest the diametric opposite -- the openness of your world defines the doorways into your language.
Dang, J P, that's an awfully weighty exposition for a sunny Saturday morning. (Anybody got an aspirin?)