Interesting and a worthy project but I'm not convinced .If you consider that an RSC like Loanhead of Daviot is 20m in diameter , the 8 orthostats (excluding recumbent and flankers) are evenly spaced , are on average a metre wide there are possible measurements between each orthostat i.e. outer edge to outer edge ,outer edge to inner edge x2 and inner edge to edge that 40 measurements to choose from when the flankers are included . It's quite likely that some are going to overlap .If there was a consistent inner edge to inner edge measurement then it would be salient but that's not the case . If it was possible to retrieve the measurements of the Barnatt /Herring experiment where the circles were laid out by eye then I suggest we would find that the same sort of results applied . It is not inconceivable that some stone circles were laid out with a rope , e.g. Lough Gur looks a possibility but I don't believe that this experiment shows it to be the case and would it it really be necessary ? It's a pity Tyrebagger wasn't included in the study it has the same number of stones as Loanhead but they are much more unevenly spaced with smaller and greater gaps than usual but nevertheless you can still find some figures that appear salient among the 40 possibles despite the fact that there is little obvious geometrical , relationships , doesn't stop it doing it's job and looking the part though .