Around 15 years ago, pilots in Aer Lingus pilots supported industrial action over the suspension of a handful of pilots that refused to accept a reduction in rest periods that had been implemented by the company but not ratified by the union and were rejected by nearly all of the pilot work force after a ballot. The Chief Pilot and Flight Ops Manager at the time was none other than HD.
Putting the intricacies of the reason for the industrial action to one side, it takes some doing when you manage to drive your pilots to the point where their level of dissatisfaction and disillusionment turns them to the point where they consider industrial action.