I suggest, not. Insurance duplication was not powerplant-driven. Jupiter began as Army+Ordnance, Thor as Air Force+Industry, with the SecDef of the day not thinking Joint. ex-Ford McNamara's notions of commonality, cost-effectiveness, and the alignment of kit with Task, all lay in the 1961 timeframe. If solid fuel had been available in 1954, USAF would still have done ATLAS + Titan, SecDef would still have allowed Jupiter + Thor + Polaris, just as B-29 flew off against B-32, and B-52 shared early R&D funds with enhanced B-36s. Insurance against techno-industrial failure.