ZD and Joseph – As I said, I don’t know much about the halachos, but I really don’t think it happens very often that L’MAASEH, the Beis Din refuses to allow someone to divorce. It may be true, as you wrote Joseph, that in halacha, there is theoretically such a possibility, but I don’t think that L’MAASEH, it happens very often. ZD only gave one example that he knows of and you haven’t mentioned any. Personally, I know tons of people who are divorced and I have not heard of a single person who wanted to get divorced but was not allowed to.
And I know for a fact that a Beis Din can allow people to get divorced even if neither of them did something wrong. There are plenty of people who get divorced because they are not a good match personality-wise, even though neither of them did anything wrong! I just checked out a divorced guy who was redt to me, and I was told by one of the Rabbanim involved that they got divorced only because of personality reasons (I decided not to go out with him, because I didn’t think his personality would work for me either.)