Mark,
Here is the difference:
Guys fly at 200%--they make money. (hurts unity but helps individual)
Postal contract--guys lose but they wanted MORE MONEY. (see the theme)
DPs--guys fly them...(hurts unity but helps individual)
So--we have proven guys will blow off union's wishes to make more money.
Now then--this LOA--does NOT make guys money. Subic guys lose tax advantage and lower Q of life. Guys going to CDG may make more money on paper, but higher cost of living wipes out many/most of those advantages. So--amazingly enough--now we have unity (mostly). This is because this LOA is a BAD DEAL for most of the crew force financially.
So--that is why the crewforce you say you cannot trust is so united--its in their individual and collective interests to say "NO". In most of your examples, it was in their individual interest even if it hurt the collective group.
As far as what to do about your leaderhip? Suggest we focus on LOA first, then let chips fall where they may. There is plenty of time this fall to pursue new block reps, followed by new MEC leaders. However, you need to know the back story and who is trying to help your cause before you just start shooting. However--a quick snapshot of the correspondence from some of the reps is probably a good place to start.