I like Dobson's book and don't disagree with it completely but parts of it. While I think it is important to draw the line at some point, it gives no room for really allowing the spouse to come back if they are prone to being too proud or embarassed to admit they were wrong.
I agree with your comments about "Love Must Be Tough". This was one of the first books I read. I didn't apply the techniques in my case because there was no OW in my case and I am pretty sure that giving my H an ultimatum would have only brought on a D and very quickly.