You've reassured me somewhat, although I'll not pretend that's the end of my worries. I've said my piece, though, so let's not fight any more.

I'm sure you'd agree that only a fool takes on board "received wisdom" without a shred of evidence to back it up. You directly experienced your many years of work with stone, and so implicitly trust your own judgement. I didn't, and so can't. I really know nothing about your expertise with stone. All I have to go on are a few photographs, and some words on a screen. I'm sure you'd behave in the same way if the tables were turned and it was me saying to you "I simply know it better than everyone else, but won't tell you why". I only press these issues for the love of curricks. And on the love of curricks I think we can agree.