Here’s another quote of important concepts from the user manual (pp. 387 ff.):
Even if there are no clips highlighted, Final Cut Express usually considers something in the Timeline to be selected. This occurs in two situations:
- If no clips are highlighted and there are no In or Out points set, clips under the current position of the playhead are considered selected for many commands. For example, if you choose a filter from the Effects menu, it is applied to any clips under the playhead, even if nothing in the Timeline appears to be selected. This makes editing faster because you don’t always need to explicitly select a clip to affect it.
- If sequence In and Out points are set and no clips are selected, any content between the In and Out points is selected on all tracks with Auto Select enabled. The selected area is highlighted.
With the exception of editing clips into a sequence, operations in the Timeline are prioritized in the following way:
- If clips are selected, any operations you perform affect those clips.
- If no clips are selected, content between In and Out points on tracks with Auto Select enabled is considered selected.
- If no In and Out points are set, the clips under the playhead on tracks with Auto Select enabled are considered selected for many commands.
- Note: Some commands operate on the topmost video clip items, regardless of which tracks’ Auto Select controls are enabled. The topmost clip items are the ones you see in the Canvas, and so those are often the items you want to operate on.