I agree with Kiwi Flyer - this sort of delay can happen anywhere, anytime - it's just "one of those things". No guarantees when you're at the mercy of the weather.

At least you didn't sit on the tarmac for hours with no food, no drink & no fresh air for hours on end like the poor folk in this thread: http://www.flyertalk.com/forum/showthread.php?t=580597

I have done the CHC-SYD trip return 4 times in the last 6 months with EK, & no delay problems (maybe 15 mins in SYD at most), so no complaints from me.

I have had a delay travelling with EK MEL-AKL (an hour or so from memory), causing me to miss a connection with NZ AKL-CHC. I knew my connection was relatively tight if there were delays, but took the risk. Didn't pay off, but not EK's fault.

I figure that if you really desperately want to make another flight (and it's not on the same PNR as your previous flights), then you should leave a LOT of spare time up your sleeve.