How is coming up with a backup plan for childcare getting "deep into relationship stuff"?
I don't have children myself so perhaps I am way off base but I thought the whole concept of co-parenting was to remove the husband/wife stuff and work together on issues that include the children.
To me, all this BS of IM's and last minute plans could be avoided if they had a reliable backup plan in place. Nobody would be forced to change plans at the last minute, both parents would know their children are being cared for and nobody has to worry about doing anybody any favors.
Again, I don't have children so maybe my view on this is incorrect.