Velveteen, welcome to Rootschat, I'm glad this thread rings bells for you. It is so frustrating, isn't it?
One of my line, the one I was working on when I originally started this thread, has my gr.gr.gr.grandmother, Ann Massey, b 1752 in Shrewsbury in Shropshire, according to several trees on a very popular site (starts with an 'A') part of a very strong line right back to the 1500s with even a sniff of a gateway ancestor (which my lowly lot don't have at all).
Only problem is that would make her the daughter of one Bartholomew Massey, and have lots of well recorded brothers and sisters - all born in Staffordshire. I was really pleased when I found all this. There are several public trees with that information, all with the same detail. I've no idea which one linked her to Bartholomew Massey and his wife in the first place, but all the others must have copied them. Nobody seems to have noticed that whilst Ann was born in Shropshire all her supposed 'brothers and sisters' were born and baptised in Staffordshire. I suppost both counties started with an 'S' so that would do!
It would have been so easy to ignore the fact that my own research showed it was a mistake and couldn't have been my Ann, and adopt the trees that were all telling the same story, after all there are a lot of them to support the claim - problem is, there is absolutely no evidence to justify them: quite the contrary. Ironically, Margery Colclough, which is where this thread came in, has now had to be deleted from my tree, because she certainly existed, but sadly not in relation to my family.
That's what I like about Rootschat - nothing but accuracy will do. Stick to your principles, it's the only way to go!