In the Metadata IPTC Template having the options for Description/Caption of Prefix/Replace/Append is very useful. I've never known why this isn't available for "Headline". If I have a group of images where I've added text to the Headline field of some images, and then decide to add more text to a group of images, I have to remember if I've added any headline text to any (or all) of these images or it will be overwritten. With prefix or append I wouldn't have to open multiple images individually to add text to this field. If a user's workflow requires only one identical headline for all images then they can set it to Replace.
