Not sure if you've had a look at this BRAC link... but if not?

http://ukra.jalbum.net/brac/About%20BRAC/index.html

Tiompan no longer contributes here; however, if you can manage to correspond through other channels.....

For what it's worth, my experience with the placement of upland cairns strongly suggests (to me) an element of exclusivity - having to be 'in the know' to appreciate what's going on.. i.e monuments apparently placed specifically to overlook a certain sector, not able to be seen from some directions when it would've been a simple matter to achieve complete visibility.