Yes, Waden hides Falkners. I agree that it's safer to speculate in terms of visibility as the simplest and most natural motivation, rather than lines on a map per se. It's easy to get tempted though - e.g. Alan's 2 lines not only meet at Silbaby but do so at a pretty accurate right angle...
I did notice, when on top of Silbaby, that as well as being able to see the other monuments, it provided a sort of grandstand view of WKLB, much clearer than from anywhere else.