I've always ran with my two inside rods at the shorter length. When I started trolling we used planer boards all the time and it was a lot easier to "steer" the fish into the free water directly behind the boat if a fish strikes your long outside line you can get it to the surface and ski it to the clean water behind the boat without worrying about tangling your two shorter inboard lines. Old habits die hard I suppose. I will fish with the same length of line out on all rods when I find a pattern the fish are liking but always stagger as mentioned above when I start my search pattern.

In refernce to planer board for crappie, I have only sen one other boat on my home body of water that is about 10,0000 acres at summer pool use planer boards. So while I get a lot of questions and conversations that start on the water, I also have also had whole bunch of boaters that do not respect my lines when I am in full spread. Double edged sword, but it is a very effective means of boating more fish, especially in pressured waters.