A really important message is delivered very succinctly in this 2 minute video. Although Alastair Campbell is talking about persuading people when speaking in public, his point is valid in pretty much any medium.
He has two interrelated he points: First the message needs to be delivered by the author "For me, today, the only communication that works is real authenticity" further, " if someone is just reading a speech they were handed... it's never going to work".
Second, in order to persuade, a position should be founded on facts and framed by accessible experiences, to build a logical, relevant argument.
"The speaker's got to work out what the main objective is of their speech," Alastair told us. "That's all about the central argument". Alastair Campbell had one of UK's top persuasive remits as Tony Blair's Chief Strategist.