It's not that unusual an idea. Pipe threads and fittings have both sides of the thread in contact, to prevent leaks. Look up "National Pipe Thread". There are lots of self-locking thread designs, such as Wide-Lock (http://www.threadcheck.com/self-locking-thread/), Spiral-Lock (http://www.youtube.com/watch?v=0hCgeimks94).
It's not that unusual an idea. Pipe threads and fittings have both sides of the thread in contact, to prevent leaks. Look up "National Pipe Thread". There are lots of self-locking thread designs, such as Wide-Lock (http://www.threadcheck.com/self-locking-thread/), Spiral-Lock (http://www.youtube.com/watch?v=0hCgeimks94).