Sometimes the facts just aren't all there and you have to make the best guess you can. If we had done as you say, we would have been defeated by the sword demon - either by virtue of us running away at all or by virtue of us being stabbed in the back as we ran away (only treave knows how it would have played out).
Well, it would not have turned out
the best way, but it was a reasonable choice of action, seeing how treave said he only added it because he was feeling generous and offered us a way out.
Sometimes you just have to make the best guess you can and go with it. It's that or run every time because we almost never really know what we're facing.
Here's what many of us did successfully guess at with our worthless meta arguments:
1. That the kiss would shock him enough that he wouldn't kill us even if we failed.
2. That WQS would give the demon an opportunity to possess us.
3. That he was a demon or possessed by one.
Ah, see, this is where our understanding differs. Those weren't
arguments, meta or not. What happened is that we came up with a bunch of guesses, and some of them turned out to be right. It was a case of a broken watch pointing at the right time, simply because one of the answers
had to be right, and between the different people we called all of them.
Ultimately, it was pure guesswork, and people who said they didn't hear a single good argument in favor of either choice were right in that they recognized it as such. None of us had any basis for their claims. Naturally, the fact that the demon was special and thus no previous knowledge applied didn't help our situation any.
Of course, that didn't stop people who totes knew B was the right call because it involved WQS.
Problem is, not enough people listened to these oh so "meta" arguments that happened to be 100% correct.
You shouldn't expect people to listen to you when you ask them to stake their life on a hunch. Both sides have failed to make a good case out of what was available. What have happened is that people were psychologically more comfortable with a 50% chance of success while they were fighting than with the same chance while they were trying to chase the dude and kiss him.
The funny thing is that the kiss that supposedly would have worked on a demon would not even land on him, so the people who were '100% correct' weren't even correct for the reasons they have themselves stated.
That's not being correct, that's being lucky.
The demon is not like our luck skill or Shulgi. treave espressly stated that the luck skill wouldn't predictably sabotage our choices and we had no idea how Shulgi or the luck skill would affect either LP.
We know for a fact the ultimate result that our possession can and probably will bring about.
Ah, but we do know how the luck and Shulgi will affect our choices. Badly. Shun will die, Yunzi will die, everyone will die etc - you know, the usual scares that people put up when they are trying to dissuade others from their chosen path. What we don't know is
if they will affect any given choice.
And that is exactly how they are alike with the Demon. What we know about the possession is that there will be little to no effect on our choices until the LP ends, because of the way we handled it. That major story-altering change you are talking about that is supposed to make it different is not going to happen during our time:
Besides, with the option chosen, the effects don't really kick in until you finish playing hero and find out that you are addicted to it.
What I would like to avoid is the situation when we no longer treat the choices on their own merits, instead acting on what would affect the DEMONZ. I am alright if you call it a bad feeling or a hunch, but I will maintain that no logical argument can be made in its favor or against it. Though if that makes it fun for you people, who am I to judge?