The dynamics of the global oil tanker market has long been studied by practitioners of System Dynamics.  This paper does not seek to repeat what has been done, but rather to focus on an aspect which has recently taken on greater importance: the phase-out of single-hull tankers by 2010, and double-bottomed or double-sided (but not true double-hulled) tankers by 2015.  In particular, questions of interest are: might the single-hull ban lead to extremely tight supply through 2010; and is it likely that the industry will overshoot the number of newbuilds necessary, leading to a crash in spot rates after 2010?  Preliminary results indicate that the answer is yes to both questions.