Got interrupted by my son on ichat. Wanted to add to my post.
The reason I think it is harder for the spouse who leaves to grow is that they are using the OP to validate them. As long as that goes on they delay or sometimes miss the opportunity to self validate.
LBSs have to in order to get on alone. It also explains why many LBS don't reconnect when given the chance. Often they grow so much the WA can't catch up.
Just my thoughts here...but maybe not so off the mark?
