" the T bars will creak and groan as they work."

Actually, if the chassis was perfectly stiff, I don't believe there would be any movement in the last 1" to generate any noise from a TB end mount hex. And TB's are always preloaded to the minimum of the chassis weight (ie no slack take up), and I would think if a TB became completely unloaded/relaxed during driving, any sound generated would be severely masked by other road/tire noises. Since everyone's chassis stiffness is different, we all might have different outcomes.

I believe a TB does shorten as it is twisted a small amount, not sure by how much or how dependent that shortening is on TB dia. Need to do some homework.