How important is collecting blurbs prior to landing a publisher? For example, if an author had a legal thriller (agented, but not yet sold) would having a list of judges and law professors who'd agreed to blurb it get a publisher's attention?
I can barely think of a single group LESS likely to draw my interest. Have you READ the stuff they call "legal writing"?? DRY. BORING. REPETITIVE. REPETITIVE. All tell, no show.
For a legal thriller if you want to grab my attention with a blurb, I want to see someone like Scott Turow, John Grisham, Lisa Scottoline, heck, I'll even take Barry Eisler (who writes about a hero on the WRONG side of the law) before I want to see a judge, or god forbid a law professor.
The point of blurbs is to have someone who's writing you KNOW and LIKE to tell you this book is yummy. KNOW means it's a writer generally not a law professor (unless it's someone like Alan Dershowitz) and LIKE of course means they write well.
You don't really need blurbs before publication. "I think this book is cool" won't hurt but it's not going to be the difference between yes and no.
Leave the professional boys to their briefs. You need some heavyweight BOXERS to jump in the ring with you.