The Introduction lists the A3 tricritical point as appearing in attractive colloids, hypernetted-chain approximations, liquid models with pinned particles, and a "variety of mean-field models." The derivation, however, specializes to a particular cubic+quartic structure with vertices {w1,w2,y1,y2,y3,y4}. Two questions follow: first, are the same cumulant identities υ1+υ2−υ4 the natural combination across all of those settings, or is that an artifact of the truncation chosen here? Second, in any one of the cited systems — repulsive colloids, attractive colloids, pinned-particle systems — does Eq. (18) yield a numerically testable prediction for μ?
Either is fine to address briefly. A single paragraph that picks one of the cited systems (the attractive-colloid HNC of Refs. [13, 14] is the obvious one) and says "in that setting, the cumulant combination evaluates to … and corresponds to the regime …" gives the reader a concrete handle on whether the formula is universal or scheme-dependent. As written, the claim of generality is asserted but not exercised on a single example.