It sounds like they're computing the most probable eigenstate of the system. Doing so on a classical computer requires doing a bunch of inefficient N-body quant

It sounds like they're computing the most probable eigenstate of the system. Doing so on a classical computer requires doing a bunch of inefficient N-body quantum mechanics with randomized interaction terms. Doing so on a quantum computer is basically just making a real-live quantum measurement. By taking an ensemble of real-live measurements, you can infer what the most probable eigenstate is, which is the "output" of the program.