I am NOT a FCP expert by any stretch of the imagination but I found THIS during a recent Google search.
In essence, this article at http://www.steves-digicams.com says about (Control – V):You can use the Add Edit Command in the Sequence menu (Control – V) to quickly make cuts similar to those made with the Razor Blade All Tool. The add edit command also cuts clips in the timeline at the playhead’s current position. The difference is, however, that the add edit command only cuts items or tracks that have Auto Select turned on. When using the add edit command, use the keyboard shortcut during playback to quickly cut clips. Each time you use the command during playback, Final Cut Pro will create a red marker at the timeline position of the edit cut. Whenever playback stops, the edit cuts are applied in the timeline.
