No, look at the examples on the page. It avoids typographic orphans, that lonely last word on its own line after a reflow. This is standard in desktop publishing (Word, InDesign, etc.) but CSS has very weak support for it...
http://thenewcode.com/946/CSS-last-line-Controlling-Widows-a...Doesn't work in headings, and not supported by Firefox. So you need JS to hack it.