Providing a much larger sample quantity to work with than other existing or proposed missions.
While scientists may be happy spending $800 million to return 60 grams of material from an asteroid (Osiris-Rex) and can likely tease out all sorts of information from that two tablespoons’ worth of material, ISRU development needs a lot more material to work with. Even the smallest of concepts I’ve seen for Option B (in which a robotic spacecraft would grab a boulder from an asteroid and move it into lunar orbit) would bring back tens of metric tons of material, both rocky and regolith, which should be plenty of material to work with for ISRU development.
I think some accounting needs to be done on the relative mission cost for the ARM versus the Osiris-Rex sample return, but on the face of it, this makes sense. This concept issues that of issue #2, insomuch that the real advantage is the local nature of the retrieved asteroid. It is hard to do real, meaty research on ISRU with very small samples, as much of ISRU’s promise is in making serviceable products and refined base material in macro quantities. That means not only looking at an extremely rare sample under a microscope or measuring its composition, but really developing space-based refining that boils off oxygen, and water, and other chemicals from the soil, and being able to build structures and machines from the orbiting ore.
That accounting is something that I think I will look into to validate my position here, but I think we’d find a cost and schedule savings by pulling off the one big deep space retrieval, instead of going far distances over and over to come home with tiny, impractical amounts of material. It’s like going to the hardware store for a nail, then back again for a board, then back for paint, then a hammer, a paintbrush…