That has not been my experience. I personally run all my distances from the waters surface, but dropping the rod tip will just add that distance to the lure, not the running depth. What I am saying, is the rod tip 2 ft out of the water, may take 6 ft of line back to the water surface. When you hook the planer board up you are just adding 6 ft more line, so you would be at 86 ft back now and still running basically the same depth. That is probably confusing more than anything.
Here is another way to think about it. At 80 ft back you are diving 6 ft. Therefor, if you raised the rod tip up 6 ft the lure should be on the surface, which it will not be, it will still be diving because there will still be about 60 for line out.
I don’t get to caught up in the number, as I said earlier, I just measure from the water surface and add that distance to my rods that are not on boards.
If 80ft to the board is working, I may run 95 ft to my rods in the holders to get the same distance, because 15ft is out of the water. Hopefullly one of these makes sense, they are all saying the same thing I hope.