To me the important point about what Buffy wanted to do in this episode is that she was correct. Caleb and the First were protecting something important at the vineyard. Just like she was right about Spike.
Buffy was not completely correct. She wasn't correct when she went into the vineyard in 'Dirty Girls' and walked right into Caleb's trap, and she wasn't correct in wanting to go back down to the vineyard all over again and nothing more than a hunch. She lacked information which is what got them into trouble in 'Dirty Girls.' When you're responsible for the lives of many people you don't just put those lives at risk on nothing more than an inkling.
The only reason Buffy succeeded in getting to that vineyard was luck. The majority of the Bringers were busy attacking Faith and the potentials down in the sewers. If Buffy had gotten her way she would have marched into that vineyard exactly like she did in ‘Dirty Girls’ and more girls would have died. It would have been an almost exact replica of what had occurred only days earlier, the reason people didn’t even want to go back into there until they had more proof.
Notice that even Faith learnt her lesson from that encounter. Before going into that vineyard she states “drop me in the hornets nest what the hell” but she learnt her lesson. They paid a price and Buffy was asking too much to expect people to blindly follow her back in there when she had no evidence or proof that she was correct. Lets also take into account Buffy played right into the First’s hands here, as it states in ‘Dirty Girls.’ That “one last push” that would send the house crumbling.
Buffy’s not incapable of making mistakes and being wrong. And as the writers state about that season, a great deal of episodes in season seven were spent on Buffy’s superiority complex and failings as a leader. That’s what helped cause the divide. She wasn’t perfect and no one should blindly follow a leader without question when wether we like it or not, Buffy led them into a death trap only a few days earlier. Against the advice of everyone pleading with her to think things through. Why should they suddenly trust her without question again? She was exhibiting exactly the same kind of behaviour that resulted in people dying only a few days prior to this episode.
As for Spike, without getting into that much again. Nope she wasn't correct. She was correct about him being able to be a good man, she wasn't correct in her complete lack of care concerning his trigger. She wasn't correct in doing nothing about it putting the lives of everyone she cared about in danger. And she wasn't correct in her bullsh#t mantra that "being a good man" would somehow eliminate the First's hold on him, when his actions were completely unrelated to free will of any kind. If no one had intervened concerning Spike the First would have simply triggered him before he could use the amulet. End of story.
Buffy wasn't smart in either instance, she was lucky. And she learnt that in 'End of Days' when she was big enough to say that what happened with Faith could have just as easily happened to her too.
