Martin Davie writes: The announcement of the choice of the Bishop of London, Dame Sarah Mallally, to be the next Archbishop of Canterbury has been accompanied by frequent references to the Archbishop of Canterbury as the ‘head of the Church of England’ or the ‘head of the Anglican Communion.’ In this post I shall explain why both of these statements are misleading, what roles the Archbishop of Canterbury actually has in the Church of England and the wider Anglican Communion, and the...