Actually, melb_boy88 and Artiste, are correct. Time just doesn't fit in this. I think Aguirre was getting off on watching which disguted him even more than breathing.
Anyway, about the only thing I would marry Aguirre to would be a shotgun.(With profuse apologizes to the shotgun for demeaning it.)
EnnisJack
what we know for sure is that:
1) Aguirre voiced unhappiness over the loss of the sheep to predators and the merging of the herds,
2) declined to rehire Jack, voicing his displeasure that Ennis and Jack "wasn't gettin' paid to leave the dogs babysit the sheep while you stemmed the rose." (quoting from the McMurtry-Ossana screenplay)
I'm not sure why Aguirre chose to watch the boys have sex for ten minutes. Maybe he "got off to it". Maybe he wanted to see who would finally go up the mountain to tend to his sheep. Maybe like a lot of people in real life, Aguirre had mixed motives and emotions.
I don't find myself disliking Aguirre as I do L.D. Newsome. Aguirre had his faults, his chief one is that he didn't provide the boys with enough food, and he provided too much whiskey. But he was like a lot of business owners, he just wanted to make a profit and gambled that Ennis and Jack would be the right fit for his goals. And, remember he hired Jack back a second time, and he paid the boys after shovedown. If you look at him from that point of view, maybe he ain't too bad. He's not going to win any tolerance awards here on this web site. But was he really so bad for someone in his business, at that time, in that location?