LMML - The fact is there is still controversy as to where the blame lies. The popular acceptance is that the airline was at fault. However, this was finding, from a Royal Comission of Inquiry, was thrown out by the Privvy council due to procedural errors - the Commissioner had overstepped his jurisdiction in his findings. Personally, I believe this version, however Air New Zealand (and some of its staf, I am amazed TG992 hasn't popped in with this, I am sure he has before) will still contend that the crash would never have happened if Captain Collins hadn't descended to low altitude, common practice, but against regulations.
As with any plane crash, I think it is rather silly to say there was only one cause. This one had many - Poor engineering practices, confusing weather, a trick of geography that made a bay in front of the mountain appear the same as McMurdo sound, the pilots low alititude flight, and the lack of any form of forward looking GPWS, which undoubtedly would have prevented the accident. It is too much to take the Air New Zealand line, and say that solely the pilots were to blame, but at the same time, you can't go as far as to say they are completely blameless.
Where the book comes in a tad one sided is that it skips over the role of pilot error, and makes only a very minor issue out of the against-the-regulations-descent. I happen to be of similar opinion to the author, so it never has really bothered me, but if I am going to be objective, I have to say that the book does lean in favour of the pilots.
Anyway, I am rambling. Read the book, honestly, it is very very good.
"So powerful is the light of unity that it can illuminate the whole earth." - Bahá'u'lláh