User blog comment:RedBack 12/Here's something you might want to see.../@comment-16241789-20151129185059/@comment-16241789-20151129185901

The point is that the sword isn't a summon; summons act independently. The fact that she's directing it with her own blade shows that it isn't a summon, because it isn't acting independently. The sword she creates in Breach is just a shaped projectile created through the manipulation of dust. We see a similar thing in Volume 3's first fight, where she uses dust to create that giant fist. It's not a summon; it's clever manipulation of dust.

The summoning glyphs, on the other hand, can create familiars capable of independent thought. The sword Weiss summoned would be capable of moving and acting on its own, though a floating sword would be a bit weird; that's why I think that she won't end up summoning the sword itself once she masters the glyphs. She'll summon the entire armor.