Everyone has their own style of reading. Personally, I tend to not read the blurb if it is an author I know. I only read it in a bookshop when I buy a book I haven't heard of. I've got such a large stack of books to read that I usually forget the blurb by the time I read the book.
In the same way I don't even read the programme notes at a new music concert until after I've heard a piece, unless it is so boring that I need something to do while I'm listening.
When I write, I often assume that my reader is smart enough to figure out what is going to happen and try my hardest to make the journey interesting. If they don't figure it out, it still works, but I plan for a worst case scenario.