Connective tissue morphogenesis has long been interpreted through a fibroblast-centric framework that assigns localized cells the role of generating macroscopic architecture. This view contains a fundamental spatial paradox: it requires individual cells to perform global geometric planning without any mechanism to perceive large-scale tissue axes. Classical interpretations of collagen-gel contraction further conflate the initial macromechanical densification of a poroelastic matrix with the subsequent biological execution, producing a persistent causal inversion. Here, I propose the Poisson-Press Theory, a physically grounded framework in which anomalous Poisson compression and poroelastic syneresis constitute the primary generators of planarization, alignment, and lamination. If hydrated collagen networks undergo these macromechanical processes under developmental or functional loading, the major features of connective-tissue architecture follow as predictable geometric consequences. This minimal physical premise restores the correct causal hierarchy: physics establishes the template, and biology consolidates it. By contrasting shear-driven lamination in the thoracolumbar fascia with pure poroelastic collapse and biological welding in the retroperitoneal fascia, the theory demonstrates how diverse fascial architectures arise from the same underlying physical law under different boundary conditions. The framework further extends to adult life, reframing occupational and athletic remodeling as continuous adaptive mechanomorphogenesis driven by persistent Poisson-Press fields.