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Here's the reason for the non-crash, imo:

Desmond, as seen in Flashes Before Your Eyes, wound up in his body, at time when he and Penny were together, with fragmented memories of having been on the island. Not just having been on an island, but having lived through the period of time we saw him in.

It caused his memories of the soccer/football game in the bar, and of the bartender getting hit in the head by Jimmy Lennon with a cricket paddle.

This episode...

All these years with an account here at Fuselage.com and I didn't know there was such a thing as a Blog

HURLEY: Where is it you think you know me from?

LIBBY: Um, I'm not sure. [sits back] I, I know it won't make sense.

HURLEY: Try me.

LIBBY: [leans forward] A few days ago I was watching TV and one of your commercials came on. It was the one with you talking about your chicken with its recipe of four deep-frying lards, and eight secret herbs and spices...

HURLEY: The four cooking lards lock in the flavor of the eight spices, by the way.
...

In 1882, barely a year after the Black Rock had made its second and final disappearance, Magnus Hanso’s son Erik made the decision to sell his father’s business. Erik was not a believer in his father’s wild tales about a mysterious island, nor was he thrilled about the fact that he had acquired funds for his journey through illegal slave trade, which had been abolished in the British Empire almost fifty years prior. In order to protect the family name, Erik made the decision to cover up his father’s...

Over time the men from the Black Rock had children with the female members of the Others. Nigel Widmore had a son named Preston Widmore, who in turn would later become the father of Charles Widmore. The societal customs of the Widmore family were passed down from father to son, even though their families back home were now inaccessible. This was done as much to preserve the family’s traditions as it was a sort of quiet rebellion against fully integrating into the Others’ way of life.
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