Sway bar with large diameter t-bars?

This isn't completely true. It doesn't effect vertical spring rate if both front wheels are moving together, if hitting a bump with just one wheel it does try to transfer some of the vertical movement to the opposite wheel.
Not really..... if the 2 wheels are not moving the same amount, that is the very definition of suspension or chassis roll..... and the sway bar raising the other wheel is adding roll stiffness to the system, not vertical stiffness. Look at how a sway bar is mounted and works; it can't exert any vertical force whatsoever.