I use this click-&-½ technique every day, and have done so for at least 15 years. It's particularly elegant with my trackball, where my left button does a normal click and my right button locks the mouse button down. So I can left-click + right-click on a word, then roll the trackball to the end of the selection and right-click again to release.

I remember when Shift-click used to extend the selection to exactly the cursor position, whether you had started selecting with a double-click or not. But the newer and more useful double-click + Shift-click behavior is at least as old as OS X itself; maybe it wasn't standard across different text engines until more recently.

One difference from Word on Windows: the default mode there is that merely dragging across text, once you cross a word boundary, always starts selecting whole words. This is interesting but not always useful, so I'm glad Apple hasn't gone that far.