VEGAS Team wrote this piece regarding the trimmer window in Vegas Pro 14

VEGAS PRO 14 BRINGS NEW LIFE TO THE TRIMMER WINDOW

The Trimmer window has been a part of VEGAS Pro since the very first version that featured a video editing tool set. However, the window has lead a somewhat conflicted life. Most users might never even use the window. After all, the very innovation that made VEGAS Pro an instant and enduring success was the efficiency with which the user can edit directly on the timeline. No longer was it necessary to bring your video into an old-school source window first to define in and out points. Instead, VEGAS Pro made it possible—and in many cases even preferable—to drag a file directly to the timeline, quickly trim the clip event down so that it includes just the portion of the clip you want, and then get on with the rest of your edit. One never even need touch a source window. Yet there are times when a source window comes in handy. For instance, if you’re looking for a short segment—or several short segments—out of a longer file, defining such segments in a source window can be a more efficient workflow. That’s where the Trimmer window comes in. Over the years, improvements have been made to the Trimmer window, but to many it still seemed clumsy and slow. VEGAS Pro 14 introduces new hover scrub technology that has opened many eyes and given users a reason to take a new look at the window. With hover scrub, any time you point your mouse at the video portion of the Trimmer window, the video scrubs to show you the frame currently under the mouse. This makes it possible to quickly—or slowly if you prefer—drag your mouse through the file and find the part you want. Read the full article here.