The composition of Chinese bitcoin demographics:
Honest money/middle class money: 10%
traders: 10%
Crooked money: the rest
Chinese money is synonymous with crooked money. All it takes is one official/business man, to start this entire rally. Officers have been caught with over $300 million dollars of cash, all from ill gotten gains.
The government is moving towards prohibiting/outlawing bitcoin because it is NEEDS to save face by stopping corruption. Corruption is so rampant in the Chinese business
For a country of 15 billion people, this is paramount. The government has to somewhat put a lid on corruption and prohibiting bitcoin is a way of saving face; to show to the world, hey we're not going to allow more money laundering... we are trying to make our country better. Whoever thinks that China feels bitcoin is a threat to the yuan... needs to come back to earth.