Yes, it is done when someone validates the link. It is to save space on the server. No use for a flash file that is linked to a bad link :)
And luckily I didn't write the plugin. My condolences with the one who did. The code in that plugin is just nasty.
I thought I might simulate the command the 'tools.validate.html' uses to validate links, with a plugin.

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Sacrifice is not about what you lose,
it is about what you gain in the process.