That's a good idea. Not permanent either.
I have a newish Kelty external frame pack on which the load lifters loosen up as I hike. Having them correctly adjusted makes hiking so much easier - it practically propels me forward. When they loosen, the pack tugs backward on me via my shoulders/collarbone. The loosening would not be from wear and tear. Perhaps it's from the angle the strap and buckle make (at a certain angle, it is designed to slip, of course), or maybe the buckle is slightly oversized for the strap thickness. IDK.