|The Ares V rocket was to lift more mass|
than any other launch vehicle in history
It seems the only redeeming aspect of HLLVs is the capability to launch huge payloads in one piece. Even if it were more expensive per kilogram to use an HLLV than a smaller alternative, there may be some spacecraft that cannot be split into two launches. However, I cannot imagine many payloads that fit this description. Unpressurized space modules can often be folded up and deployed once in space, while pressurized modules can fit inside smaller launch vehicles if they are made to be inflatable—like the modules under development by the company Bigelow Aerospace. If these separate modules could autonomously rendezvous and dock with each other after reaching orbit, who would pay extra to use a heavy lift launch vehicle?