I was staying well clear :-) Everyone was doing a great job of enlightening the bloke. As I don't do a great deal of rock art I love seeing it posted here, but I was taken aback by the chalking.

I know university professors who have chalked RA in the last five years. What I said to one of them is unprintable (even for me!)

Life's too short to get angry with folk. Headucation! Headucation! Headucation!