SRS, from reading your posts over the years, it is also clear that your dogs get a lot of quality time and attention.

I made the statement about invisible fences, but on reflection, dogs behind physical fences can be just as bad. Too many people fence their yards as a substitute for walking their dogs and otherwise spending time with them. "Hey, let's fence the yard. Then we can just open the door when rover has to crap and not bother with taking him for a walk." So, it's not the fence that creates the barker. It is the emotional neglect.