The thing is, like the pro-democrats, the pro-establishment camp is also rivened with internal divisions and power struggles. There is no love lost between the pro-business end of the camp, like the Liberal Party, and the more pro-union/working class end of the camp that Tsang and his brother originally belong. Only the HK government, and above that the Liasion Office and Beijing, holds the pro-establishment camp together through it's directives and instructions on how to vote in Legco, etc. Some in the pro-establishment camp have a little more leeway to stake out an independent position while others are under the direct control of the CCP and must follow their orders to the letter.