Joseph, I agree with you 100% that the more Yeshivish the community the less divorces (in general, imho). In fact, that is why I always get upset when people attack the more Yeshivish ways of dating as though they are to blame for the rising divorce rate.
BUT, I think that there is a big difference between saying that the more Yeshivish/Chassidish ways are the reason for the high divorce rate (which as you pointed out does not seem to be substantiated by the facts), and saying that there are people who would be better off going out more often or in different ways.
As I keep pointing out, these things are very individual and everyone has to do what’s right for him/her.
One thing that is bothering me about this conversation: If it’s untznius for people to go out more than a handful of times, or to have more casual dates (even though it’s for toeles), why is it okay for men to be talking to women online (and telling them that the way they date is untznius)?
Personally, I think that both things fall in grey areas of halacha, which doesn’t mean that there is no right and wrong, but it does mean that it depends on the individual and the situation and therefore only the person himself can make his own cheshbonos (by weighing the ideal against the reality).
I totally agree with you that dating has to be as tznius as possible, but it also has to be effective, and what that necessitates is different for everyone.