They are also talking about a reduced version of Orion as a life boat for ISS crews. How do they get a reduced version of Orion into LEO?
Most likley an Atlas V. Because the the Orion-superlite would be unmanned at launch there will be no need for a man rated Atlas V, for that launch atleast.
The Atlas V has the serious potential for being just such a medium class, economy-of-scale example. At this point we have ULA saying they want to man rate and make it avalible for multiple manned craft. If we had Orion-superlites, Dream Chasers and all the other NASA and DoD payloads flying I think it would reduce the cost of any indavidual launch significantly.
It's kind of funny though because we want competition in launch providers to reduce costs but on the other hand if everyone is using the same launcher you get reduced costs as well. I suspect in the rocket biz the right combination of both would be advantagious for both costs and increased innovation.
