一个一个点要花多少时间？而且各部分批到不不同的地方汇集，不同时间，地点出发，清点人数之后怎么样核实，记录等等，不是那么容易的。Even today for the US armed force, with computers and network support, it still takes a lot of effort to keep track of troop deployment. Let along 60 years ago, semi-regular Chinese armies.