Technically, I don't think that any old cross can be called N. "Sabre" other than the original. Otherwise it becomes more of a GREX and there is an important horticultural distinction. However, all I'm saying is that someone may have made the same cross, and called it "Sabre" even though it shouldn't be. The whole 'clone A', 'clone B' thing is a bit confusing, if you ask me but it's not without its merits: For one you know the exact parentage of the plant, but you also know what to expect from each specific clone. I think it's a good compromise between cultivar names and grexes... but to the uninitiated it can be confusing as hell. Also it can lead one person to think that they're getting one plant and be swindled with another plant.