FluffThorrent

This is a very interesting topic that has also been discussed elsewhere (hence why I'm writing here - this video is really interesting and got me looking for more discussion). As to your theories, I think you could be missing something which would save a lot of headache: the historical Silk Road wasn't held by any one nation or power. It stretched all the way from Rome to Hong Kong, Samarkand to Mombasa. It would frequently adjust to war and conflict and had several routes over both land and sea. If you want the mod to specifically incorporate the Crimson Caravan company, that works with or without the Legion, even the NCR. The Hub - representing centralized trade - was already present and had formed its own pseudo-city state before Shady Sands rose to prominence. Given enough manpower and time to create settlement networks, even a northern route through the Salt Lake region to Dakota could be formed, avoiding both nations (but might run into others...). As the video also hints (as is my own belief), Bethesda must have had something of a "Jet Road" in their lore design, explaining why we see Jet and bottlecaps in use in DC and Boston when the series has only portrayed separate US coasts, with no game connecting them.