But it did. Just as people were starting holidays, finishing their Christmas shopping, or winding down with a drink on the last day of work. The physical damage may not be as bad this time round, but it is another psychological hammer blow.
People are not just shocked, as they were when the previous big quakes hit. They are angry. They had started to return to normality, begun repairing homes and restarting businesses, were looking ahead to a relaxing break - then abruptly they were snatched back to the hellish days of February and June.
People were again spilling out of buildings, fighting through traffic gridlock, frantically trying to reach loved ones on overloaded phone networks, crying and embracing each other in the streets - and all while the aftershocks continued throughout the afternoon.
Suddenly liquefaction was the buzz word again - small fountains spewing out more of the water and sludge that became so familiar in the previous quakes, deluging streets and properties.
Robin Thompson summed it up as he trudged around his sodden section: "No one wanted this for Christmas."
Of course, many will again be questioning whether they can stay in Christchurch. Especially those families coping with terrified children. And who can blame them?
But most of us will stay, knowing that eventually there must be an end to it all. Even amid yesterday's shakes there were signs of the resilience that defined the city's people after the previous disasters.
Pensioner Norma McKenna, 85, could still manage a smile as she showed the Weekend Herald around her liquefaction-hit property yesterday.
She had just walked back from the local supermarket where, during one of the quakes, "my trolley moved and another lady helped me so I wouldn't fall down".
Her home is still under repair from the previous quakes; now her driveway is flooded and she has fresh patches of sludge across her section.
Mrs McKenna won't let it ruin her Christmas, and I'm sure others won't either. But once again, we will have to be on guard.
