"but cannot even put any details on what the trigger will be...

"but cannot even put any details on what the trigger will be other than vague assertions"

I don't think you read the original article as it clearly states the following possible triggers:

1. Property Investors realising that their capital gains are only being fueled by other property investors entering the market, much like a Ponzi scheme. Once the game is up, property investors will be leaving in droves.
2. Baby boomers, a major driver in property investment increasing prices, divesting their property as they retire
3. An increase in interest rates caused by higher borrowing costs by Australian banks caused primarily by the GFC
4. A slow down in China, possibly caused by the reduction in consumer purchasing from Europe and the US, will have a direct impact on commodity prices and have a direct impact on the Australian economy. Any pressure on the Australian economy would likely have a flow on effect to the demand and pricing for housing.
5. The abnormally low number of people per dwelling in Australia as a result of the housing over supply can comfortably scale back to more historical levels, further compounding a housing price reversal.

If any of the above starts to impact on Australian housing prices it will have a domino effect.

To require people to state exactly when the bubble will burst shows a lack of understanding of the problem. The bubble will burst when the weight of the above factors become too great and the camel's back breaks. No amount of economic modelling can show the timing due to the large number of external unknown factors.

What can be determined however is that the above risks are genuine and will increasingly put pressure on Australian house prices until the bubble does burst. At the very best for property investors, there's little / no chance of gains in the medium term.