Well, as unions go, the IAM is one of the worst to deal with.
The best line I ever heard was this, "If you tell a mechanic to do something for the 'good of the company,' you can go ice skating on his corneas as his eyes glaze over."
The IAM approach to compensation was this...you have X number of airplanes, and they need Y number of mechanics. If Eastern loses 10 airplanes, then Braniff will get 10 more. And those will be IAM guys. It really doesn't matter if they are painted blue, or silver or chartruse. And we don't care who we work for. Therefore, talk to the pilots or FA's or service folks...we ain't listening.
This has kept mechanic income realatively stable (which probably puts them ahead of ALPA) but, they are mercs when it comes to any concept of loyality to the firm. Its been beat out of them by management. However, its now brought them power by the hour, 3rd party/3rd nation maint. etc. The old calculus of the minimum required number of mechanics industry wide is becoming a quaint notion, like a pension.
But then, I have enjoyed living a middle class life in a first world nation. At least I'll be able to tell my kids what it was like.