That vehicle was operated at the edge of, or in excess of, its design and test parameters (depending on the model and passengers). That extra two hundred and fifty kilograms of passengers in a one tonne car could be significant. Surely a case could be made to a jury that the vehicle was so obviously compromised that no amount of concentration could have ensured safety. But now we'll never know.
If I strapped a baby-grand piano onto the roof of a VW Golf and rolled it and people died, well, wouldn't I have to face a jury, regardless of my on-road skills? The decision to accept those circumstances and drive anyway should not be divorced from the assessment of driver performance and culpability - which must include judgement.
I hope this isn't a case of "she's already learnt her lesson", as in last year's case of the SMS-driver who killed a cyclist. Such a view undermines community confidence in the law.