Q. A central London bookshop has kindly invited me to be one of 30 authors signing copies of our books at its Christmas customer evening. I feel it would be rude to say no, so I’ve said yes. But I went to last year’s event at that same shop, and saw the excruciating sight of some of my favourite authors sitting alone and unvisited at their signing tables, while crowds were queueing round the shop for Gyles Brandreth.