Interesting responses to this thread. Here were my own thoughts:

I have always been pretty good at putting myself in other people's shoes for things like this. I'm not as good with bigger pictures -- unless someone else is very close to me in terms of world views, familial relationships, past social experience, etc, I'm not always great at putting myself in someone else's shoes and figuring out all the emotional pulls other people have in their personal lives. But for something like this, it's not at all difficult.

Crotchedy A possibly did not know what was going on with the lines. She did have to pass right by the head of the line, but I was not yet paying attention at this point. She might have thought we were all deciding on our orders before getting in line. She might have not thought about it at all and, rather than being Crotchedy A was actually Oblivious A. Heck, I wander through crowds in an oblivious daze myself, because my mind is seldom to content to focus its energy on such mundane things as standing in line at McDonald's. I wasn't, in fact, until I realized something was going on worth paying attention to. Then again, Crotchedy A may have known exactly what she was doing and cut purposefully. I could buy any number of explanations, good and bad, and as I am compulsive about giving people I don't know the benefit of the doubt, practically to a fault, I'm not about to attribute her with an unsavory motive she may not have had.

I don't know what I would have done if I had been paying attention before it was too late and she was already ordering her food. In fact, if not for Indignant B, I wouldn't have ever learned she had cut at all. But I can very easily put myself in Indignant B's shoes. I am not very confrontational in person, but if I had *seen* her cut in front, I likely would have said something. It depends on how introspective I was feeling at the time: today, I was VERY introspective, so I might not have done more than one of those audible sigh-grunts people do when imposed upon -- enough to convey the message, assuming Crotchedy A would have heard, but not one that would elicit a helpful response. In a more exuberant mood, I would have said something. (I like what a friend of mine once said in a *different* McDonald's -- "Sure, barge ahead. Lines are for silly people.")

But the fact of the matter is that I was not paying attention. Indignant B was scolding before I realized Crotchedy A had cut, and by then Crotchedy A was already half way through the order anyway. When Indignant B looked through the line for support, I didn't react, I suppose, because I was also, as I said before, putting myself in Crotchedy A's shoes and giving her the benefit of the doubt. Up until her replies to Indignant B indicated she didn't care one whit.

Indignant B was wrong for pushing it after the initial moment. Nagging and bickering at her afterward, when (1) the offense had already been pointed out, and (2) when it was too late to do anything about it, was a waste of effort. Let it go. Not worth the trouble.

Snickers C and D, frankly, might have been Sam S and Dave P, if we had been in that line together. Thinking it funny is by far a preferable and less personally stressful response than over-indignance.

Cutters E and F, I am sure, are almost completely without blame. I didn't care for the smugness of Cutter E's replies, but I'm certain he had no idea what weird thing the lines were doing. And Profanity G is a jerk, as everyone seems to agree. Worker H is someone I see every time I go into that McDonald's -- the only employee there I recognize from one visit to the next, and I wasn't kidding when I said she was working too hard to notice any of what was going on. She's easily one of the best McDonald's employees I've dealt with. She wastes no time fooling around -- her every thought and move is directed at serving people as efficiently as she can.

Observer I was miffed when Cutters E and F cut, but Observer I also recognized that they didn't realize what they were thinking and therefore did not say anything at that point, either. Profanity G's interjection discouraged me from voicing an opinion even slightly akin to his anyway.

Bottom lines: (1) I possibly did not act optimally concerning Indignant B, but I'm not particularly sure what would have been better, considering how the late the point at which I became aware of what was going on.

(2) *I* was able to put myself in everybody else's shoes and see where almost everyone involved was coming from and gave them the benefit of the doubt. I was able to recognize a situation that would do neither myself nor anyone else much good by getting riled up about and therefore choose not to get riled up about it. Why don't people do this? If we assume Crotchedy A cut in ignorance, why couldn't Indignant B have been nicer about approaching her the first time and not approached her at all the second? Why couldn't Crotchedy A have realized her error and been AT LEAST apologetic and possibly also moving to the end of the line? If Indignant B had been more polite, Crotchedy A might not have been so crotchedy. If Crotchedy A had been more polite, Indignant B might not have been flustered enough to chew her out the second time. Even assuming Crotchedy A cut on purpose and was rude on purpose, if Indignant B had seen fit to let it roll off her back instead of bickering about it after the initial exchange, both would have left happier.

The whole thing reminded me of Terry Brooks' "Running With the Demon" series. I read book two in the trilogy 4-5 weeks ago. For those not familiar, it's a dark sort of fantasy, set in the present day, and posits that such incidental acts of impoliteness and imposition, like not holding doors for people or cutting people off in traffic, are actually contributing toward the eventual subversion and destruction of the human race. It's a compelling idea, and they're good stories.

At any rate, I just wish people weren't so easily offendable and not so hostile to people who might point out that they're not -- gasp -- incapable of making a mistake.