History has shown it's easier to axe a wholly owned. No court, no questions asked. At least with Skywest, ASA, and Pinnacle, they would have huge court battles to fight, because it would be "company vs. company."
It's a touchy subject and I wish no one a job loss, but it would seem that the most cost efficient and painless option for Delta as a company (but not for pilots) would be:
Dissolve Comair & dump Mesa
Give XJs 900s away to Skywest, ASA, and Pinnacle
Use Compass as a flowback relief valve for NWA would-be furloughs
Use Mesaba for EAS lift in the Saabs