It's well-engineered, Reg--you should patent it!
You must have read hubby's mind--he wondered if any of the cats were able to jump over the insert.
Introductions went pretty well again today. Our schedule was crazy, so neither cat got much attention until after dinner. After we ate, I brought Dusty in to run around the family room for a while, then locked her in the family room kennel. Got JD up and let him loose. They sat and stared at each other for a number of minutes, with JD getting up and moving closer in small increments. Finally, he sort of sniffed her through the bars and sat down again.
Dusty reached through the bars and playfully tried to touch him. He spurned the advance, but at least he didn't slap at her! And, in less than 20 minutes, he had gotten nonchalant enough that he came up in my lap for his usual evening snooze. She lay down in the kennel and had a nap. So they aren't hyper-alert about each other any more