The xml from the rss feed has a channel element with two child 'link' elements: 'link' and 'atom:link'. Even though one has a namespace prefix, Go xml unmarshaller sees a conflict. See also local name collisions fail and issue on github.
<?xml version="1.0" encoding="UTF-8"?>...<channel><title>Forum - Sixty Second Idea to Improve the World</title><link>http://www.bbc.co.uk/programmes/p02nrvz8</link> ...<atom:link href="http://www.bbc.co.uk/..." />