Are edits destructive?
In the Arrange Window, no edits are destructive. In the Edit Window, only edits that involve processing (NORMALIZE, FADES, REVERSE, TIME or PITCH CORRECTION, SAMPLE RATE CONVERSION, e.g.) are destructive. There is a single layer UNDO function, however, and when you exit the Edit Window, ADAT/Edit will prompt you whether to UNDO your edit or make it a permanent part of the audio file. Edits in the Edit Window such as setting you r Start, End, and Anchor points are nondestructive.