Delta management decided to not let Delta pilots go to Comair without giving up their number.. Delta could have MADE Comair the puppet airline take the guys. So it was Delta's fault.
I don't agree, but assuming you are correct, should the ComAir MEC have supported or disagreed publicly with management's decision? Even if it had no bearing on the outcome.
(and also asked for more and larger RJ's as part of that agreement and then sued for relative seniority integration).
The problem was/is not with the managements of the airlines, it was with the ComAir MEC's actions relative to that. Capice?