As well as bricking up the shattered walls, some of the agencies have added a new feature not envisaged by Kuito's original planners: an underground concrete bunker, reinforced against future possible attacks.
To call this a risky procedure would be an understatement, however -- venturing past a certain point raises the real possibility of bricking the device, and HTC's bootloader tool already puts limits on post-unlock support even when it's blessed by carriers.