So, I am looking at a paper by Rosenfeld, "On a problem of C.E. Shannon in graph theory", where he gives necessary and sufficient conditions for a graph $H$ to satisfy $$\alpha(G \boxtimes H) = \alpha(G) \alpha(H) \qquad (1)$$ for all graphs $G$. Here, $\alpha$ represents the independence number, and $\boxtimes$ represents the strong product. But, he does it in terms of linear programming which I am not great at. So, I'm wondering if what he did corresponds to some known graph parameter. Below I transcribe the relevant portion of the paper for completion.
Let $G$ be a finite graph. $V(G) = \{g_1, \ldots, g_n\}$. Let $\{C_1, \cdots, C_s\}$ be a fixed ordering of all the different cliques of $G$. Define $y_i^{(j)}$ to be 1 exactly when $g_i \in C_j$, and 0 otherwise. Also, let $$ P_G = \left\{(x_1, \ldots, x_n) \quad \left| \quad\sum_{i = 1}^n y_i^{(j)} x_i \leq 1, \quad x_i \geq 0, \quad 1 \leq j \leq s \right. \right\}. $$
Theorem: A finite graph $H$ satisfies (1) for all graphs $G$ if and only if $$\max_{x \in P_G} \sum_{i = 1}^n x_i = \alpha(H).$$
So, my question is simply, can this be stated much simpler (to someone who doesn't know much about linear programming) in terms of some graph parameter, i.e., is that linear programming problem a way of describing a known graph parameter? Can the theorem simply say if and only if $\alpha(G) = \beta(G)$ for some graph parameter $\beta(G)$?