OK, so I'm not that brave after all. After a week of not sleeping (and I mean NOT SLEEPING!) we broke down and bought two crib tents. So many people recommended them to us, and I have to say they are Brilliant! Not only can the girls no longer get out of bed, they can't drop their pacifiers, steal each others' blankets, or throw toys at each other. We are sleeping better than we did before all of this started.
The truth is, they almost seemed relieved that we took all of that freedom away from them. Toddlers really do need structure!