There are some doubles on which the lever started in the center & will remain there irregardless of wear. I currently have three which are like this; an early Lefever side pivot opener, a British J P Clabrough & a Geman J P Sauer. These later two are both double underbolted with doll's head, over 100 yrs old, have no built-in wear compensation, both appear well used but both lock up tight & on face.

Miller/TN
I Didn't Say Everything I Said, Yogi Berra