Duddo Five Stones 2
Image by BigSweetie

there has been some opinions that the grooves were "helped" but yeah one look at the local geology tells you it's just the way they are.

Of course, I reckon it was deliberate that they were stood end-on so that it got the "best" erosion...

Another place where this is really well illustrated is St Cuthbert's Cave:
http://www.themodernantiquarian.com/post/10882

Cuddy's Cave, just up from the Bowdens, I forgot about that one. Used to have CnRs didn't it?
I like to think there's a few hidden in those trees in the nearby Kyloe Hills too.

>> Of course, I reckon it was deliberate that they were stood end-on so that it got the "best" erosion...

Too right! I think a very good understanding of how the stone would weather was held by those that erected them. I came to the same conclusion after seeing all the Carlow grooved stones. Wonderful!