That comment hints of wanting to see Greek as a vehicle of everyday communication or of wanting to see the language taught along the lines of communicative need, rather than patterns and structures. I'm a little ashamed to say that even after so many years of reading, I would still be more comfortable filling a page with memorised tables than with contiguous and meaningful text. Now, these past few years, trying to talk to a child who does not yet know the world beyond the confines of her own senses is also a much greater challenge than I could have anticipated - the fall-back that Greek doesn't have a word for such and so doesn't make sense."Shirley Rollinson"] I can learn all the fancy grammar and chant the paradigms, but if I can't ask for "a gallon of gas and a dozen eggs, and how much does it cost?" (or the GNT equivalent) then the language becomes a series of hurdles rather than a means of communication.
Specifically arising from this discussion though, let me ask, Is there a topic in the New Testament, for which all or most of the grammatical structures are used, but the vocabulary is limited? or perhaps one in the wider Koine? I guess that for Latin, it is war. Does that hold true with Koine Greek too?