Your link is not working but those taking out big mortgages are taking a big risk(there are risks everywhere)
Keep in mind that the property market (even in Auckland) is a bit like a share--it can have good fundamentals but that wont save it if other share markets tank--dont think it isnt possible to have a housing shortage and a situation that creates a drop in prices --All it would take is a housing crash in China and Australia.
The Auckland housing market has been very good to me over the years(along with some hard work) but I am under no illusions that it is only a one way street.
There are solutions other than waiting if you are keen though--one is to buy in a less desirable area and improve and rent it -obviously you have to do research though.