AFAICT: There's a large net gain compared to the energy emitted by the lasers. There is still a considerable loss compared to the energy consumed by the lasers.
While at it: I don't think the NIF approach will ever be applicable to commercial power generation on Earth. But I hope it will be one day applicable to a fusion-based rocket engine.
While at it: I don't think the NIF approach will ever be applicable to commercial power generation on Earth. But I hope it will be one day applicable to a fusion-based rocket engine.