If Australians are underwhelmed by our less-then-brilliant national broadband network (NBN), with its different classes of service, we should look no further than a Barracks Heights backyard in February 2011.

There, at a barbecue for Liberal Party faithful hosted by Kellie Marsh - a party activist, not yet the mayor of Shellharbour - we heard the vision for a two-tiered NBN from Malcolm Turnbull - then opposition communications spokesman, not yet the prime minister of Australia.

It was the emergence of "fibre to the node" (FTTN) - cheaper than extending the fibre optic network to each house under Labor's "fibre to the premises" (FTTP) plan.

At the barbie, Mr Turnbull told the Mercury he could see why businesses might need 100Mb per second, but could not think of an application where a household would.

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"Obviously, if you've got a business with 50 people using computers at the same time, it's a different thing," he said.

"There's no point building infrastructure to people's homes at enormous expense that does not give them additional benefit.

"It's like a guy that's living out on the bush somewhere ... at the end of a dirt track. He'd love the council to seal it. Now the council can seal it, and then he'd be sweet. Or the council could build a six-lane freeway, and he'd also be sweet. But there would be no material benefit at all between the sealed single-lane road and the six-lane freeway."

Obviously.

This was reported by the Mercury but wouldn't be officially announced as Liberal policy for two years. We can only guess why Mr Turnbull chose a suburban backyard to explain why suburban houses didn't deserve top internet speeds.

Perhaps we didn't realise how different this would be from the NBN we had voted for. Perhaps 100mbps seemed like a world away. FTTN - while an inferior technology mix, using much copper cable, would be quicker and cheaper, the logic went.

Former NBN boss Mike Quigley has since said this technology mistake was a "fundamental problem" which would mean higher maintenance costs and lower performance.

More recently, Mr Turnbull has said a government-built NBN was "crazy" and a "waste". But under his plan we have still spent $51 billion - without getting the utmost benefit.

This blunder has cost Australia in productivity and possibility. Anyone still argue against fast internet at when WFH in 2020? Or tele-healthing with a doctor?

If we could travel back in time to that Barrack Heights barbecue, what could we tell Malcolm about the future? And do you think would he listen?

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