While Stenfors didn't know it at the time, August 9 would later be dubbed "the day the world changed" as the start of the worst financial crisis since the Great Depression.
The author of Barometer of Fear - which tells the inside story of the "greatest banking scandal in history" - said his "fairly boring" job trading interest rate swaps became the epicentre of a frenzied trading floor fuelled by rumour and fear.
"A lot of this was about figuring out who could possibly go under. Which bank is in bad shape? How do you figure that out? You rely on hearsay and rumours to an extent," he said.
"We traded billions and trillions with each other and it was impossible to know which banks were exposed to another bank in the whole financial system."
The chaos Stenfors describes cuts to the heart of why some experts believe the crisis took on a "life of its own" so quickly. With no way of knowing who was exposed to how much toxic debt, sources of funding dried up.
By August 9, respected French bank BNP Paribas had frozen A$2.55 billion worth of funds citing an "evaporation of liquidity". Former Northern Rock boss Adam Applegarth called it "the day the world changed" after the European Central Bank and US Federal Reserve injected A$113 billion into financial markets and it proved not enough to calm panicked investors.
One month later, Northern Rock suffered its first run on the bank in 150 years as customers queued to get their money out. By September the next year, Lehmann Brothers had declared bankruptcy marking the start of the full blown crisis that would spread throughout the economy.
At the time, Stenfors said he "couldn't see the world was going under" and was simply worried about his current trading position. Two years later he was left exhausted after years of waking up to early morning phone calls and suffering from RSI after intense computer training.
In 2010 he cited the "enormous workload and a prolonged lack of holiday" as rationale for hiding his positions which ultimately lost Merrill Lynch more than A$575 million and earned them millions in fines from the Irish financial regulator.
"I was in pain physically, chest pains, weight loss, both mentally and physically," he said about the workplace where weakness was taboo.
"It's an environment where you don't really talk about it that much .... At least then, you didn't talk about weaknesses where you open up and say "I'm a wreck". I think many, many people were. I don't think that was unique."
AMP Capital Chief Economist Shane Oliver also pointed to the lack of transparency and "financial engineering" that saw the crisis take on a "life of its own" in August 2007 when banks had no way of knowing "what subprime skeletons were in the cupboard."
"The whole issue was this combination of financial engineering and a lack of transparency," he said. "Whereas if there had been transparency around who was exposed and who wasn't, I suspect there would have been less of an issue."
While Australia famously survived relatively unscathed due to a proactive fiscal stimulus package, low interest rates and demand from China, a recent household income reports shows wage growth has remained stagnant since 2009.
A decade on, governments around the world remain consumed with slashing deficits leading to austerity measures in parts of the UK and Europe. It's also sparked major debate around financial regulation, corporate responsibility and executive pay with questions over whether enough has been done to change the toxic banking culture.
Stenfors said the crisis taught him he had lost his "moral compass" and now advises would-be traders the job is "going to change you as a person". Now an academic, he said "banks were doing something completely different from what they were supposed to do" and recognises his own role in "sustaining and promoting" the environment that led to it.
"Financial markets had become too much about backstabbing, not serving clients, taking too many risks ...[It's] a painful wake up call for how do we put things right again?"
As for whether it could happen again, Oliver is in no doubt regulators and finance workers should be on guard.
"Of course it can happen again. History doesn't repeat but it does rhyme .... There will be another one but it won't quite be the same as the previous one."
