My guess: the P-80 was relatively well characterized in its standard one-engine configuration. The idea *probably* wasn't to seriously propose a two-engine design, but just an effort to see what would happen had it had two engines of a recognized type. I suspect the end results weren't terribly impressive. More thrust, but not only was the aerodynamics blown out of kilter, but the roll rate would have been trashed due to throwing so much mass so far out from the centerline. Summary: "are two engines better than one?"Why not use a Meteor ? or better, a P-59 ?
The Meteor would be harder to convert since its engines were buried in the wings. As for the P-59, it was totally obsolete and didn't fly very well to boot. The P-80 was the perfect platform for this sort of madWhy not use a Meteor ? or better, a P-59 ?