I was having a conversation about the effectiveness of traditional blocking techniques the other day on the blitz martial arts forum ( here ), when something that I should have realised years ago dawned on me.
The goju blocks (and those of most other styles of karate) move towards the centreline with the first arm, and then away from the centreline with the second arm. The first arm intercepts and deflects attacks to the centreline, and the second hand disrupts and clears. This works just fine for straight attacks, but is just as effective against non-linear attacks. It also ties in beautifully with a double-hip motion and angling of the centreline away from the target to gain added speed, power and control.
As I said, bloody obvious, but just something I'd never thought about before.