EPA's landmark greenhouse gas rules for power plants took effect in late December but legal experts and others are clashing on the rules' long-term “durability” as they face their first court test this year ahead of likely Supreme Court review and, assuming they withstand legal challenge, implementation by a new administration. Critics of the regulation say a new president, especially a Republican, could easily reverse the regulations. For example, former Sen. Phil Gramm (R-TX), currently a vice chairman with the...