You cant prove ANYTHING!! And for your information, I spent the whole weekend installing a TiAg grille! And I did quite well if I do say so myself..Only 3 of those plastic clips are on my driveway pavement... Well, 3 from each side that is....
And by the way, being in a museum would be indicative of one being culturally aware...Not me man...Im in Cambridge twice a week, but thats only because there are more pubs there than bathrooms....
If I find out who the guy was, I'd buy him a pint though!!