Crap, now I'm going to have to reread the book. (I finished it in November)
It was stated that the Webbing operation requires it to be charged with electricity (specifically, not just energy) to be able to catch the Ether like a sail, which is why they need to be energized by the core crystal.
Also, I believe they said the reason some ships couldnt do Dives is that they were too massive and so it would rip the crystals out of their mountings to try to decelerate out of the dive.
Excellent observations. From an Electrical Engineering PoV, it implies a voltage gradient in the air that the "webbing" has to be charged to generate force against, however, the force is transferred at the crystals judging by the mount observation.
I had thought that the webbing gets an induced "current" that then gets channeled to and harnessed by the crystals to drive the ships.
Of course, induced current in a conductor is how AC motors generate torque period, but they don't require the conductor being acted upon to be pre-charged.
bagga now I've gotta review some of my notes from the Gwen/Journeyman scene too.
Edit: Note to self, read the published version of chapter 28 and 49...