Seen at Derailed by Darry (I cannot get used that name, I just cannot. It's like lguest versus Rustivisor (eat this analogy, sports fans (I suppose I could add a link... But they never do it when they discuss sports!)).):

One thing ef does is that at no point in time are the multiple stories at the same story progression point. Using the three heroines as the barometer, they are either at a high point, a so-so point, or a low point, but they are never all three at a high point or a low point.

It's true. The ef is designed like a braid.