That is what I was thinking. I may try and bleed the wheel circuit on the front. I have not been able to push fluid on the rear MC to the ABS yet. Something wrong there.
It has been three years since I did my Spiegler work so my memory is a little foggy, but I do remember that the rear control circuit was a major PITA. I think I spend 2-3 days getting that bled enough to pass the bleed test. The front was easier, but still a pain and I had to ride the bike several times before the levers fully regained their feel. I think there are lots of places for air bubbles to hang out and the vibration of riding the bike helps dislodge the last few hold-outs.
I believe I posted my experience here somewhere, maybe at the end of my clutch replacement thread, but my recollection is that it was a bear. As to the feel of the brake with the key off, I think mine feels nearly the same as with the key on it is just that the same amount of force provides a lot less action at the caliper with the ABS off. I dont believe the feel is much different and I cant think why it would be given the schematics of the iABS that John has posted prior. Then again, my system is now fully bleed. With air in the wheel circuits, I have no idea how that might change the feel in the control circuits.
I would suggest that you take a break from the control circuits and have a go at the wheel circuits assuming you can get enough pressure in the control circuits to activate the ABS pumps. Then cycle back to the control circuits for another round. Sometimes just letting the bike sit overnight will allow time for some of the small bubbles to percolate up to the master cylinder in the front. The back is more troublesome given that the master cylinder is at the low point of the system, but the air should migrate upwards eventually.
I seem to recall that a I had a hard time getting the rear master cylinder to begin to pump fluid to the ABS unit. It was almost like there was a bubble in the reservoir line that was blocking fluid from even getting down to the master cylinder.
I know that I came away thinking that if I was going to do brake line replacements often on an LT, I would invest in a good pressure bleeder to get started.