Better "Dark Frame" Subtraction in PhotoShop

David Pearson, a night photographer from Orange Park, FL, told me that he has developed a technique to automatically remove hot pixels from long exposures without turning them black.

(illustration by David Pearson)

His blog posting describes how this PhotoShop action works, and provides a link to download it for free.

I understand how it removes background pixels, but I don't understand how it would remove background noise (one of the main goals of dark frame subtraction). I haven't had a chance to discuss this with David, yet. I'm assuming that you would normally run this action to remove hot pixels, then run the standard dark frame subtraction technique to remove background noise (which must be big problem shooting at night in plus-90 degree temperatures in Florida).