The Washington Post has an excerpt from the book, which will be available Tuesday.  It looks like quite a tale.  Hedge clippers to trim a cracked nozzle.  Felco?  

Seems like the main advances are in computer hardware and software, which is how high g soft landings are possible.

Though probably materials as well.

Space flight is still a matter of launching fuel. Lots of fuel. And, oh, a small payload.