Well, a laser melts stuff in a controlled manner so it kinda falls outside of what they meant by "cut". You can't use traditional glass cutting tools because tempered glass will shatter, just like you can't bend cold tempered steel. But if you heat it to a high enough temperature, then it loses its hard and brittle properties and you can rework it - though once you let it cool down it's no longer tempered steel. Same thing with the glass, except you heated it in such a localized area most of the panel is unaffected by the change.