Have you tried the procedure for "disabling" it (I believe the manual specifies holding the traction control button for 10 seconds until a special notification is received in the driver's console; it is described in another thread somewhere)?
I don't know if that shuts it off completely, but I am very confident that breaking a wire has a very high risk of shutting down many other systems as a safety mechanism if it detects a traction/stability failure; think engine entering limp mode and telling you to visit a dealer, and not being able to reset it yourself without the encrypted dealership computer connection.
This may be something that an aftermarket module that modifies the truck's computer can offer in the future, such as the Tazer DT.