Gale,
I think it's a hit of miss kind of thing that someone does just on the off chance that you'd find a link to someone else researching the same family line. I don't think it helps unless both you and your matches have researched back far enough to be able to connect the ancestors and see if anything new is learned.
In my case, I found some others who had German ancestors around the same area that my ancestors came from but I also found some matches with people who's known ancestors were all traced back to Britain. They didn't know of any ancestors in Germany.
Best wishes, Pam