Newthings, I am inclined to say "yes." To tell for sure, one of our dyno jockeys could leave the drive shaft in and jack up the front of the VX during their next 2wd pull.

Maugan, if this is something that you knew for certain, please save me the trouble of figuring it out for myself. If it weren't for Tone's post, I would have completely ignored the ball/ramp mechanism, which would have led to big trouble had I decided to test my 'new' 2wd mode by doing donuts in the parking lot.

This doesn't mean that we can't modulate the clutch to go above the 15% that it seems to like (in '2wd') however.

It just means we can't have true 2wd. We might be able to use locking hubs to disconnect the wheels, but that driveshaft, diff and those axles will still turn.
I still want to pull the signals off of some wires to confirm this, but I believe that this (the mechanical connection) is certain and un-bypassable (?) in a non-SOTF transfer case.

There is a TOD Trooper in a friends' junkyard nearby...