A great discussion on marriage is on Fr. Tim Finigan's Blog in two parts at this time.
http://the-hermeneutic-of-continuity.blogspot.co.uk/2013/02/marriages-created-and-sacramental.html
http://the-hermeneutic-of-continuity.blogspot.co.uk/2013/02/convalidation-and-sanation-and-civil-law.html
Here is one of the priest commentators notes in part. Thank God for clarity from SOME priests. And, I am glad to see I was spot on with the Church's position in all of this.
From a commentator:
A further consideration with convalidations and sanations is the question of consent. In a convalidation, it is deemed by the Church to be the beginning of the marriage. If - as is no doubt the case with many marriages these days - couples have a few children and then adopt artificial contraception, and intend to have no further children, then it invalidates the convalidation, as there is no intention to procreate present at the point at which the marriage bond comes into being. This is a real problem with convalidations when children are in their teens, for example. With sanations, this problem is overcome, but one has to presume that the consent to marriage is still there at the point at which the sanation takes place. With both convalidations and sanations, it is often the case that, where they are requested, the couple may be going through a rough patch, and either or both parties are seeking something that will cement the breaking relationship together. Indeed, this - I believe - happens a great deal with cohabiting couples, who seek to get married in order to shore up a breaking relationship. It usually does little other than to hasten the split, and leave the couple in difficulties