Several leading consumer interest groups responded enthusiastically yesterday to news of the Justice Department’s antitrust probe into cable operators use of data caps and other tactics against online video competitors. Free Press called it “great news for consumers and cable’s competitors alike.” Public Knowledge said, “Media and telecommunications giants…should not be able to take advantage of their size and reach to eliminate competition and to harm consumers through data caps which favor some content over other.” But in a widely discussed client note, Bernstein Research analyst Craig Moffett warned that the DOJ’s action could backfire, causing greater harm to online video providers and raising prices to consumers. According to Moffett, the likely response by cable operators will be a wholesale shift to usage-based pricing, which the FCC has already blessed, which could raise the cost to consumers of using Netflix and other streaming services. VideoNuze’s Will Richmond, meanwhile, argues that the feds are overlooking the real harm to consumers from current cable industry practices: the cost of live sports programming. No good deed goes unpunished.