Why Was the Office of Chairman Abolished?

The power structure in the party in 19 82 was more pluralistic, rather than autocratic. The most sacceptable choice for all power groups involved at that time was to abolish the office of the party chairman and to divide the power. So now, that was a really excellent history. Can you talk a a bit about why the title was abolished? Was this a functional bureaucratic structuring? Was this symbolic? Why did dung feel the need to get rid of the title?