That's not true. She was nursing under a blanket and the flght attendant still didn't like it.
As for the other stuff I never really thought of it but it makes sense. Let everyone board and then let the kids board with their parents.
This isn't going to work with SWA's normal high load factor and no assigned seats. The flight attendants are going to eat up all their time that they saved having to reseat passengers to accommodate families. The airport is already family unfriendly enough without having to have your kids sitting by themselves next to a stranger.