This feature would either add a new type of lever to the game or add new functionality to the lever itself. This feature would allow for the lever to be switched into the "on" position, which activates redstone, doors, and trapdoors as normal. The difference is that , when switched into the "off" position, the lever would forcefully make all redstone it is connected to become deactivated. This would include being able to "lock" doors and trapdoors using this lever. This would add to redstone builds by incorporating an easier way to keep everything stable while still in the assembly state. You could place this on TNT to make it so the TNT wouldn't activate through any means short of Flint and Steel. There are other uses I can see this being used for, including creating combination locks much more easily than the current models.