The "40 years in aviation" expert on US MSNBC tonight, ex PanAm captain Tom Bunn has just posted this:
Asiana Crash At San Francisco - National Fear of Flying | Examiner.com
In there he states, "As to height, there is more than adequate guidance; the runway sends ILS signals that show whether or not the plane is on the proper glide path. There is also a visual device to provide proper glide path information."
Seems the Capt needs to check his NOTAMS. Amazing how TV puts on such shallow publicity seekers