Chen Xi did not give much thought to Jia Xu's question. Perhaps Jia Xu was in his excited phase, or perhaps he had caused trouble again and wanted to throw the blame before anyone found out. Who knows?
After all, none of this mattered. What mattered was Chen Xi confirming Li You's assessment, and Liu Ye arriving at the same conclusion: Yuan Shao intended to drag the situation out. In fact, Yuan Shao was likely to adopt the same tactic as Zhao State back in the day—dragging out the grain supply—and on top of that, Yuan Shao had an obvious advantage compared to Zhao at the time: his grain resources could sustain the delay far better.
Frankly, this was the scenario Liu Bei least wanted to see, which is precisely why the concept of mediation was introduced!
