Wellll...I don't know Chinese and have never studied in China, so I can't speculate in that domain. But I wouldn't be so quick to infer specific techniques from their memorization speed -- they're fluent in a very similar written language, and it's much faster to learn things (in any language) when you're fluent. They also grew up in a...well, let's call it a memorization-intensive learning environment.

The only things I can say with confidence are:

  * focus on words
  * learning words becomes faster in *any* language as you gain proficiency
  * learning radicals helps you recognize kanji, and is a good thing to do

That's really my complete set of advice on the subject.