[ QUOTE ]
[ QUOTE ]
Jack's plan to get them free was pathetic, especially considering Juliet would prefer Ben be dead anyways.
[/ QUOTE ]
From Jack's perspective I think it was a good plan. He doesn't know they're on alcatraz, and
he knows that the others besides juliette do NOT want ben dead.
[/ QUOTE ]
I don't think you can say he knows that. He might suspect it, but he doesn't know it.
If what Juliet told him with the placards is the truth (or even resembles the truth), he's trying to use Ben's life as a bargaining chip with people who may actually want to see him deposed, and who might be indifferent to his death.
He might have figured, or guessed, that Juliet is lying / making a move for the leadership, and is
hoping that threatening to kill Ben might force acquiescence from the rest of them, but he surely can't be certain that every Other is 100% loyal to Ben.