RevMike,
Actually the Deep Curl appeared AFTER the Fusion, as a component bullet. They were both made by Speer, with the same equipment.
For some reason the then-PR guy for Speer decided the "new" bullet needed a new name, and came up with Deep Curl. Quite a few people suggested that since the Fusion was already pretty popular, they stick with that name--or perhaps Fusion with some Speer addition. But he refused to listen, and within a few years the Deep Curl disappeared.
Of course, another reason for its demise was Speer planned to discontinue the Hot-Cor, replacing it with the Deep Curl--which they initially thought could be made (and sold) as cheaply as the Hot-Cor. That turned out not to be the case, and they also usually offered different Deep Curl bullet weights than Speer had offered in the Hot-Cor for decades. The rest is history.
