Most don't react to that kind of message - I'm generous and assume they're probably still in work or have a family to look after but, basically, let's face it, most people can't be bothered to do the work. Hence the huge lack of family trees.
I wish I shared some DNA with you Jill. I'd be confident your info would be correct. I'm still in full-time work and don't speak to my colleagues during my lunch-breaks as I'm busy on various family history websites. If they bore with me with football results or celebrity gossip I send them into a glassy-eyed torpor by explaining census returns. I'd be more than happy to accept some input from my contactees, particularly if it was evident they had done their own research and not copied it from another family tree.
But to perfectly honest I actually really enjoy the searching, results and surprises - even when it turns out to have little relevance to me. I now know that there were a large collection of lighterman and watermen around Bermondsey called Wheeler and that various members of the Lane family (perhaps mine but nothing proved) lived with and sometimes married into them. I know a lot about various Lane families in Bermondsey, Lambeth and Camberwell - how they connect to each other and what they did for a living. Should I ever prove a link to my illegitimate Mary Ann Lane the work is largely already done and saved.
It would still be much easier and perhaps more rewarding for my own family research if people would
a) post a tree and if there was some sort of disclaimer on the websites whether they were actually interested in their own genealogy or simply ethnicity
b) have a public tree that at least had surnames and approximate dates so there was a starting point for us both to try and find a match.
c) had a tree rather than a late flowering twig. 4 people isn't a tree
d) That Ancestry would indicate which country the match is from. A small national flag next to the name would be perfect