I'm not sure if I am requesting a bug fix or a new feature, but it would be very useful if the navigation lock would also work when the 'breadcrumbs' in lister titles are clicked. At the moment, it seems that no attempt is made to follow the path change, even if you simply do the equivalent to one GO UP. This needn't actually check that the folder names match (using GO UP doesn't do this anyway), but just take the required number of upward steps in the other lister.
This is one of my two 'favourite' ways of losing synchronisation. The other is to navigate too quickly when one of the locked paths is an FTP site. I wonder if a navigation delay could be introduced when the navigation lock is engaged, so that potentially synchronisation-breaking navigation operations are not initiated until both listers have obtained their folder contents?