Genuine liberation works on a generational timeframe; it does not happen spontaneously, and it cannot be established and secured overnight. It is more important to seize the hearts of the people than to seize control of land. In this respect, the strategy of Al-Qaeda is wiser than Da’esh.
No one in Syria would accept to fight against Jabhat an-Nusra. They are planting seeds that will be cultivated over decades. They have established a stronger foothold in Syria than Da’esh, even if Da’esh appears to be more successful because of their state-like control.
In my opinion, the speed with which they are trying to consolidate power and the force they are using to accomplish this, may ultimately undermine them and alienate the population.