The window blind thing is supposed to be over the wing exits only - the theory being you wouldn't or shouldn't open the emergency exit into the flames. But the flames outside will really stuff your little old ladies night vision anyway - or light and darkness gradient (whatever). How long does it take to lift a window blind? Two seconds, maybe? So why do the airlines persist in propogating myths and pulling up the window shades at top of descent in preparation for the mythical crash on landing in flames. If they are that worried about a crash then why not go the whole hog and instruct passengers to take up the brace position for every landing. Just in case, you know.