Delete all unused clips by moving all clips to trash and then "reveal in browser" from timeline
I have been looking for a way to clean complete projects by removing any un-used clips to reduce library space, but never really found a good solution... until I discovered something recently by chance...(using latest FCPX 10.3.1)
Seems like if you do "Move to trash" on a clip that is in use, it will disappear from the clip browser, without being actually moved to trash. Then if you select that clip in the timeline and select "reveal in browser" it will pop back up in the clip browser, and the "undo" menu will show that last action was "add clip to event".
So what I do now is to select the Smart Collection "All Video", then Cmd+a to select all clips, and Cmd+delete to move all to trash. If I now look in the trash, all the unused clips will be there, and if I look into the final cut library structure all used clips are still in the original media folder. However the "All Video" Smart Collection shows no clips. Now, by selecting each clip in the timeline and pressing Shift+F (Reveal in Browser) the clips pops back into the "All Video" clip browser/Smart Collection.
My question is: Is this an acceptable and safe way to clean a project from all un-used clips, or is this just some glitch, and might mess up the project or library? I read in apples fcpx help that move to trash will never move used clips to trash, but was surprised that they anyway got removed from the clips browser, and I had to use "Reveal in Browser" to make them re-appear.
MacBook Pro with Retina display, macOS Sierra (10.12.2), final cut pro x 10.3.1