As I was working on de_sacrilege I needed a face breaker function. I assumed (correctly) that there were many available on Scriptspot. So I found one that most closely matched my needs. It didn't fit what I wanted directly, so I made a few enhancements and shared the update with the original author, which are now part of the latest download.
Features I added:
+ Added Randomization to the Shell Inner and Outer width. When using randomization, the Shell modifier is not an instance between objects.
+ Updated Shell side texture coordinates to use the Interpolation mapping.
+ Added option to only detach selected faces. When on, objects with no face selection assume ALL faces in object.
+ Added the break function to the Undo List.
+ Changed logic so that when the object is not being deleted, it won't be converted to a collapsed Editable Poly.
The shell randomization and working on selected faces were my primary needed functionality.
Check out the Face Breaker (http://www.scriptspot.com/3ds-max/scripts/face-breaker) script.
Here is an example of what I used the script for: notice the broken blocks on the left side.
(https://www.wallworm.net/examples/sacrilege_face_breaker.jpg)