Because writing assessment's present is bound to its past (Elliot, 2005;Poe et al., 2018), scholarship has pointed to the need for more critical inquiries of local "assessment ecologies" (Inoue, 2015) to better understand the effects of past injustices (Hammond, 2018;Harms, 2018). In understanding how opportunities are allocated unjustly within processes like articulation, compositionists must be willing to understand how postsecondary ecologies have systematically attempted to deny opportunities for certain student groups. This article does so by examining the 1935 Michigan Committee on the Articulation of High School and College English, a committee in charge of redefining readiness for first-year writing across the state of Michigan, led by Professor Clarence DeWitt Thorpe of the University of Michigan. The work of Thorpe's committee has been an under examined component of historical assessment ecologies in the Midwest and beyond. Under Thorpe's guidance, this committee shaped assessment to function across numerous institutional spaces. Utilizing this historical example, this article illustrates that narrow emphases on the ways local ecologies shape opportunities are insufficient for identifying how opportunities are structured. Instead, scholarship should be more attentive in understanding how any given local ecology is situated within a broader system of interinstitutional ecologies that define the boundaries and formations of opportunity within the space.