I know somebody who met him on Eurostar once. He has virtually no creative input in the programmes. The crew turn up ahead of him, they do cutaways, establishing shots, brief those who will be interviewed etc.. He then turns up, does the walk bys, the 'looking out of the window' shots and the pieces to camera. The rest of his involvement is in the narrative voice-overs. The programme is rarely shot in sequence and he just reads/voices script.
He clearly has developed a style with which he is comfortable in his new career, but I doubt that his skills would go very far in the direction of a professional director.