"body may well adapt to the process of drinking large amounts of olive oil. "
I agree that this may explain the lack of stones.
"Anyone who has been at gallbladder surgery or postmortems could sift out the likely Gallstones and then the rest could be analysed. of course some of the objects will be genuine Gallstones - but that's not the point I'm making."
I lost you here ... can you re-explain what you wanted to say?