I can't believe that a tubeless road tire would be more comfortable or have any practical (as opposed to theoretical) advantage other than puncture sealing with a fluid like Stan's if it works at high pressure. But, my experience is strictly on ATBs.
I do know that mounting/dismounting any tire on a "designed for tubeless tires" rim is a real pain at least for 26 inchers. For ATB's the tubeless tires are heavier because they are thicker. Thicker tires are lossier and stiffer tires and eat up more energy. More energy than a thin tire with a tube? I'd have to see the numbers to believe there's a practical difference.
It's worth experimenting to check it out. I do that a lot. You never know.
Al