I love "cohabitation ad experimentum". I just googled it as I had never heard the expression before, and all the results were related to this survey. Apparently it means "a way of trying out marriage before making the commitment", which we probably could have guessed.
Speaking as an outsider, it seems clear that the church has a massive problem, which is that the world has moved on, while it hasn't. People - even Catholics - don't care any more about sex before marriage, or contraception, or divorce, or homosexuality. They just don't regard them as moral issues. And Catholics have stopped being frightened that they'll go to hell if they don't obey the church - as far as I can tell, most Christians in this country don't even believe in hell any more. So how is the church going to reassert its historical authority? It's going to be tricky, I reckon.