Of course there is asymmetry between China and Japan, but Japan currently is the one with the upper hand. It is shrinking instead of growing, since China is catching up. That Migleader guy is too cocky on this topic. Can't believe he was writing this back in 2006.....
Even today, Japan still has the upper hand, in terms of technology and production ability. Except it has a leash on its neck and the master is Uncle Sam. On the other hand, China's civil and defence sectors both have great demands, this will definitely encourage improvements in the ship building sector. On the other hand, China does have upper hand in some extremely high tech areas, like satellite (linking to ship), missiles, and radar technologies.
But as of this moment, Japan still got more ships and they are extremely new. They add a heavy sub every year, each with tonnage almost able to match nuclear powered counterparts.
To some extents, China is still like the former Soviet Union. It has the super high tech things, like space and nuclear technologies, but lacking in some basic things. Although USSR could design the world's best subs, they still had to import CNC machines from Japan in order to make the propellers.
Japan's technology is much more rounded than China.
But after all, Japan can never surpass its bottleneck, that is Uncle Sam. On the other hand, China can develop as quickly as it wants to. The sky is the limit.