We never stop learning do we… And the learning of karate can only be a result of physical training itself. One of the, dare I say, ‘hardest’ points of karate, is ‘physically learning’ to relax. ‘Masterful relaxation’ means to control the body perfectly, via eradicating unnecessary muscle power. Therefore the result of proper junansei training is “economy of motion to achieve maximum effect with any karate technique”. Here is a link to a past article I wrote on this topic: http://andrebertel.blogspot.com/2007/06/from-hardness-to-complete-softness.html
Sensei’s rendition of Nijushiho (I’m sure you’ve seen this many times) is an unparalleled example of junansei. Click here: http://www.youtube.com/watch?v=QHVHdhGWtuM.