December 28, 2009 was the final day to submit comments on the Environmental Protection Agency’s (EPA’s) proposed Prevention of Significant Deterioration and Title V Greenhouse Gas Tailoring Rule. This is the rulemaking in which EPA proposes to “tailor” the Clean Air Act’s (CAA or Act’s) Prevention of Significant Deterioration (PSD) pre-construction permitting program and Title V operating permits program so that they can be applied to carbon dioxide (CO2) and other greenhouse gases (GHGs) without spawning an economically-chilling administrative morass. The Tailoring Rule is an eye opener, because it reveals, or rather confirms in spades, that the Supreme Court’s decision in Massachusetts v. EPA has created an almost bottomless well of “absurd results” — disastrous consequences that EPA can avoid only by poaching legislative power and amending the Act.