Wrenching a Crafting Interface off a cable dupes the variable cards within it.

Step 1:

• Build a small network with a Crafting Interface on it.
• Put some recipes in the Interface.
• Use a ID Wrench, or a TF Crescent hammer to remove the Crafting Interface from the cable.
• The Cards from within the interface drop, along with the interface.
• Put the Interface back on a cable
• The cards are also still within the interface.

Happens in SP and MP, using:
Integrated Dynamics: 1.0.11
Integrated Crafting: 1.0.6