I'm not too sure if you really meant this to be in the "humor" section (outside of the smiley faces) since I don't really sense anything funny about it, but I'll keep it here for now (instead of moving it to the feedback section).
The reason why I use Japanese phrases is due to the fact that some of the phrases contain a lot of history and cultural background and would be very, very difficult to sum up in just a "literal" translation. Oftentimes, the knowledge of the phrase itself is as important as knowing its meaning -- kind of like picking up on all of the English aphorisms that I had to learn when I first came to the States. The fact that these pithy yet deep phrases exist often shows how important such concepts were to people.
For one, I don't think using Japanese phrases in the context of discussing a Japanese martial art is "stupid" in any way.
Just my thoughts.