2 articles about Hagane no Renkinjutsushi
The subject by its numbers · The Pairing
Two — cooperation. That is the reduction of this name, and the shelf it is read from.
What the 2 brings is cooperation. The reference files it as a negotiation. Whatever else this section is doing, it is doing it with the 2's search for balance between competing sides.
The Pairing — two names, two markets, and everything negotiated between them →Part 110: The Alchemic Triad – Edward, Alphonse, and Winry Through a Numerological Lens
Part 87: Commanding by the Numbers — Levi, Mustang, and All Might's Archetypal Leadership