Is there a deeper meaning to the final fight scene -spoilers-

I read somewhere that the movie converting to black and white could symbolize the fight of good and evil, much clearer distinction between them at least. The fighters crawling in the mud reminded me of them getting dirty and all stained. I remembered the sensei's words that the black belt should never be stained. So I thought that Choei, the one that was not involved in the fight, would inherit the belt. Or we could be reading too much into it, may be it was just to make it look nicer, more artistic.

I think that the black and white fight-scene was a kind of review of the entire movie and the main point of the movie.

Giryu and Taikan are both wearing their white karate gi. White representing innocence. Then they get into the mud and all dirty. Taikan being the first to fall into the mud and Giryu following him. Symbolizing that they eventually both stained their black belts.

When the fight is over and the saturation comes back, you can see red poppies around them on the ground. Red poppies symbolize death and rebirth. This fits perfectly, because Taikan dies and Giryu is "reborn" by finally understanding his master's teaching.

(Grissom): -Are you a terrorist?
(suspect): -Depends, are you terrified?