The only thing that makes me nervous about OVERKILL is it may delete a line that is actually supposed to be on top of another line. The project we are dealing with asks for polylines and then closed lines wrapping around those polylines.
Ignore the arrows, but this is the kind of scenario we run into frequently.

Or say a closed line for a cabinet up again a wall and then a closed line for a countertop, and the lines against the wall are the same length, just different layers. Would overkill delete one of those lines? There are red lines underneath the cyan lines.

This is why I was wondering if there was any way to identify overlapping lines before deleting it. I am ok with overkill deleting all those little 0 length lines that sometimes appear.