According to the on-line [manual](http://dl03.vegascreativesoftware.com/manual_vp16_en.pdf) page 57 of this commercial software this is only true if you:

1. have selected the <kbd>Copy media with project</kbd> checkbox and
2. Clicked the <kbd>Save</kbd> button

##for all your projects!

If you forgot to do that with just one, the answer is:

> No, deleting the original file *will delete* it from all of the projects where you did not click that option.