latjoreme - Great points!
I don't think that Jack got Ennis drunk per se. Ennis is not a child, Jack couldn't have 'made him' drink the whiskey if her didn't want to. Also, Ennis was the very responsible type, I presume he would know when to stop drinking, especially since he had sheep-tending duties that night. IMO, Ennis and Jack had been having a real swell evening, sitting by the fire, Jack serenading Ennis with his ..umm..singing
, their relaxed conversations kept flowing and so was the booze. When Ennis makes the comment about 'never having the opportunity', I figured he was speaking in code ... and Jack very cleverly read between the lines.
I think that Jack was yearning from early on to be allowed to stay in the camp with Ennis. When Jack was bitching about Aguirre 'having no right to make them break the rules', and "we both oughta be in this camp!", he was indirectly confessing his dire need to share the camp/tent with Ennis. And then when Ennis offers to switch with him, Jack looks at Ennis as he walks to his horse, he says: "You won't get much sleep, I tell ya that" - as if he was giving Ennis another chance to reconsider and stay back at camp with him. Of course, Ennis just utters a muffled "ya" and rides off.
I am positive that Jack was always looking for an opportunity to share that tent with Ennis. So on 'that' night, when Ennis was plastered, his defenses considerably lowered, Jack saw his chance to get Ennis to stay and seized it! Ennis was clearly in no position to ride a horse, let alone watch the sheep all night. Did Jack use the situation to his advantage? Definitely!! Did he set up an elaborate plan to get Ennis drunk? IMO, no. He went with the flow of events and tried to nudge things forward with Ennis, and it worked!
I bet when they were actually in 'the act', Jack couldn't believe his azz..i mean..eyes!
I love that entire scene, it speaks volumes; from their drunken conversation till the 'morning after'..