“Vegas is for putting together video-clips.”
As is every other video editor I’ve ever worked with 🙂
First of all, why do want to do “destructive” editing?
The philosophy of most NLEs is to leave the original clips intact.
That gives you the option to do whatever you want to the original clip knowing that, no matter what you do, you still have the original clip as a fail-safe backup.
It’s only when you render the completed project to another format that you’re doing a “destructive” edit as, once it’s been edited and rendered, you can’t undo any operation you performed on it.
It’s also destructive as Edward described above (trim, render new, delete original).
You also have the option of only capturing the clips you know you’re going to use on the project.
I’ve done 10 min. videos where I’ve shot over 2 hr. of material. I then sit down, screen all the footage and only capture what I need for the project.