It proves that you should always, as a minimum, send for the certificates of your direct ancestors, no matter what the expense. Dud certs can be advertised on Rootschat (there's a board for them somewhere).
I've been meticulously through the more remote parts of my tree checking for errors. Just three. One was genuine - two Elizabeths and my relative married the more faraway one, easily done. One where the bride had been married before (funny, she didn't mention this on the record) both these a matter of correcting a surname. And one where a boy seemed to have a different mother's maiden name to his siblings - puzzling, as I have his baptism - turned that that birth was to another marriage of those surnames and mine seems to have been left off the register.
The only bad mistakes on my tree, years ago, were where I'd trusted information provided by other researchers, seemingly more experienced than me and competent. Not so. New-found cousins can be a great source of info but always ask if they have the certs!
