Something to think about...
I don't know what went through the minds of the Flightcrew. Being a Boeing pilot, I'm going out on a limb here assuming the GPWS system has similar callouts. I think that mabye the crew, knowing that they would be getting a "TOO LOW FLAPS" warning, disregarded the "TOO LOW GEAR" warning as it's substitute. You know, in this situation your "expecting that damm warning to go off", and being human, heard what they wanted to hear.
How many of us are guilty of that.
But for the Grace of God go I......
Fly safe