How Do the Japanese Butcher Fish?

Today, I’m geeking out over the latest post on The Japanese Food Report, an excellent blog that feeds my insatiable cravings for Japanese culinary esoterica. 
They’re talking about the sophisticated technique for butchering fish that extends the process of rigor mortis in the fish, and thereby enhances its umami (that is, savoryness, as distinguished from sweetness, saltiness, sourness, and bitterness also detected by our tastebuds). Good sushi is clearly about more than the freshness of the fish.
For anyone who’s obsesssed with raw fish, this is a fascinating read.