TONGUE bobbling aimlessly across his lips in a rare moment of dumb-struck puzzlement, there was no escape for Bill.
Breakfast TV's boy prodigy Karl Stefanovic (the bloke is 41, by the way) had him by the Shorten curlies.
Cheap-shot puns aside, the moment Stefanovic asked, "How old were you when Labor last delivered a surplus" was a reminder no amount of pre-interview role-playing can prepare a pollie for all eventualities.
Shorten was caught off guard, made a weird "ohwu blurblurble" noise with his tongue and responded: "I guess I was an adult."
Makes a great ringtone when played on loop, if you are in the market.
That Today Show fumble will be dredged up mercilessly in the coming days as the Liberals fight to discredit Labor's economic credentials.
But hang on, what about Malcolm Turnbull's brain-freeze moment in April when he was incapable of explaining why poorer Australians were better off with negative gearing?
"Common sense," was his unscripted explanation.
Off-the-cuff cranial cramps like that are asphyxiated gasps of fresh air in this orchestrated campaign, even if they do make our leaders look like dullards.
Shorten should have known better, though.
In 2011, Wayne Swan was asked the same question.
He floundered pitifully and admitted he did not know, before knocking over and smashing a glass full of water in the radio studio.
The answer is 1989-90.
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