Japan has an advanced, technology-driven economy. There's nothing inherently vague about the language: it can be as precise as any Western language when the situation calls for it.
OTOH, the difference between technical Japanese and literary Japanese is quite dramatic. I'm only a very beginning student of the language, but I find technical Japanese much easier to read. The vocabulary is harder, but it largely dispenses with the grammatical constructs that give literary Japanese its layers.
Was your audience composed of people based in California, or in Japan? My Japanese friends here in the US seem to appreciate American directness.
They were all based out of Japan and had flown over for the presentation.
While I agree that it is possible for Japanese to be just as detailed as other languages, I find it interesting that as you begin to get more and more detailed about IS concepts, everyone I've dealt with begins to leverage Chinese terms. "Hara" and "koshi" are rather ambiguous terms that can describe a fairly large area of the body and don't contain the detail that you need to really discuss what's happening in the body. What is the Japanese term for "kua" for example? The "one point" as Tohei described it is often associated with the dantien, but I don't think this is a good 1:1 association.