I would vote for "something isn't fully understood yet" also.
I have no idea whether the rage exploit "conceptually" would or wouldn't work because I can't connect to the phone after rage kills the adb server (on the phone). I've already run "adb kill-server", which kills the local server on the windows box, but since there is no adb usb interface, it can't connect to the phone when I next run "adb shell"
If I could figure out why that is happening, at least I could look at some log files to see if those give some clue.
I can see in devmgmt.msc (Windows Device Manager) that after the first few USB unplug sounds, the ADB Sooner interface is gone. However, unlike in V9, it never comes back after the second set of USB plugin sounds.
I think a good first step is to figure out how to get connected to the phone after rage runs so we can figure out what is going on.
From the way zefie worded his post, it seemed he was saying the whole VC root procedure was dependent on the V9 recovery kernel, which happened to not get updated for some unspecified reason with the method of update that was being chosen earlier.
If that was what was going on, it would have been very nice to have specified that in the beginning, as it would be very tenuous to have a root procedure that depended on the recovery partition not being updated due to some bug.
Also brand new phones would presumably not have that problem/"feature" and would have the newer recovery kernel/partition installed at the factory.