Oops, forgot to reply to this: Oh, speaking of memory-rummaging, I've been rummaging in the last few days about Charles' visit to England, given all the reliable-looking sources that have turned up. I think *maybe* my past self conflated "don't believe the legend that he was at G3's 1760 coronation" with "don't believe the legend that he visited England again in the 1750s and converted to Anglicanism."

Ah, okay, that explains it! I'd never even heard the claim that he was at G3:s coronation. Well, it's never a bad thing to hunt down the primary sources anyway...