I also have a couple of tangential ideas for weighting endorsements:

- Expertise match: e.g. Elon Musk endorsing a rocket engines book vs history book

- Strength of endorsement: e.g. "This is the best book I've ever read," vs "I liked it."

Editors do try to get and use _relevant_ blurbers. And a weak blurb probably wouldn't get used unless they really had nothing else. Also, the first readers of blurbs are booksellers and reviewers, not readers, who may pass over a title if no one is willing to vouch for it. If you present a title to your sales team with no blurbs, they will make frowny faces at you.