It had a precedent that goes back to 1970. Many American evangelicals were caught by surprise by J I Packer’s involvement with and defense of Evangelicals and Catholics Together. The first ECT was vague, misleading, and even gobsmacking. The second was, for those committed to the faith of the Reformation, infuriating since it didn’t really address the problems of the first. One of the questions I’ve heard over and again since 1994 is “How could Packer be involved in this and defend it?” The answer is partly in his history, which Martin and Carl (via video) explain. Alister McGrath’s biography of Packer is also illuminating in this regard.
UPDATE: 20 October 09 see Martin’s illuminating post on Packer’s 1959 address on “Evangelism and the Sovereignty of God”