We can agree to disagree but running Auto allows slippage of the friction plates (which are just automatic trans discs) so you get (more) friction material in the fluid. This is also what the special fluid does, ie dampen chatter
Yes, it's always pumping that fluid and transferring power but it's not a straight mechanical connection like a more "primitive" case.
Even in 4lock where it mashes the clutches tight they CAN slip if you're stuck and really working to get out of a hole or something. No different than a manual trans clutch slipping, really. Plenty of JL's with the "AWD" case burn up the clutches trying to escape a bad situation