Despite the sustained effort of about forty years to analyze Subjacency, to date, there has been no principled account, with the most recent attempts faring not much better than the initial proposals. It is also significant that the seeming arbitrariness of Subjacency has been used to argue that syntax could not have evolved gradually: One does not see why evolution would target a grammar with Subjacency, when its contribution to grammar is not transparent, let alone its contribution to survival. As put in Lightfoot (1991), “Subjacency has many virtues, but … it could not have increased the chances of having fruitful sex”. This article turns the argument around, and proposes that subjecting syntax to a gradualist evolutionary approach can in fact shed light on the existence of Subjacency effects. It thereby offers a reconstruction of how communicative benefits may have been involved in shaping the formal design of language.