Cool, thank you both very much.
I see there's some more discussion on that blog here as well
http://brian-mountainman.blogspot.com/2011/12/those-periglacial-stripes.html
I think with most of the controversy being whether they're periglacial or otherwise, rather than that they actually exist? But I suppose if they exist there it doesn't mean they couldn't exist elsewhere nearby if they are indeed natural?
And that photo is certainly very groovy, they are indeed very undulating. How nice that you got to see them in person. They run with the length of the avenue, that's right isn't it? The programme implied they stop shortly before the henge. Do you know where they stop in the other direction? Do they go up to the 'elbow' in the avenue?
It's all very interesting is it not.