One big name per story is usually considered to be sufficient. So when two of them appear in one by-line, it can certainly be called a scoop; so that's what we'll call it. H. L. Gold and science-fiction go together like a blonde and a henna rinse. Robert Krepps is also big time. You may know him also under his other label—Geoff St. Reynard, but a Krepps by any name can write as well.