My understanding is that it was just a study and never a serious mission proposal. Prety much like the many Mars mission plans put forward over the years.
What's nice is that such a lunar Gemini can be put together using the existing meshes in Orbiter. Not perfect but doable.
From my perspective, the most interesting mission is the direct lunar landing, using [SIZE=-1] 2 Apollo Service Modules and a LM descent stage.
» The thing goes up on a Saturn, and [/SIZE][SIZE=-1]the translunar injection is done by S-IVB stage[/SIZE], with the assistance of the first Apollo SM.
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» The second SM get you into lunar orbit and down close to the surface.
» The LM stage performs the final landing and lifts of from the Moon to a transearth trajectory.
It's interesting because there are no dockings, and it's like a rocket with many many stages
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As I said, doable in Orbiter with the parts we already have, but perhaps a little too complex for what's worth...
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