“The process of getting blurbs – which the US journalist Rob Walker has termed “blurb-harvesting” – is thought, by some, to be a necessary part of modern book publishing. You send the manuscript of your book to another writer, hoping they’ll like it, hoping they will give you a favourable comment to put on the cover. It’s a weird transaction. No money changes hands. There is only one unspoken convention: if somebody blurbs your book, you should not blurb theirs.”