Not knowing the situation completely, I can’t say yes or no with regard to the youth’s actions. It could be that they did account for a reasonable chance of a life being lost and saw that that was not the case. Or they could have simply been wrong.
I gave some general guidelines back on page 2 of this thread. They were:
So, in the above situation, we simply need more information than Shoshanna was able to provide. Was there oncoming traffic? If so, I’d say yes, stop the car. Is the rest of the hill vacant and no reasonable chance of anyone being hit by the car? Then I’d say no. Furthermore, maybe they reasoned that the person could hold the car and others would be along shortly to help. Or they could have acted improperly to begin with. In any event, they could have done what Keeve suggested (enlist someone else to help).
I looked at the responsa you provided, but have not yet had a chance to really consider it. While the author is correct that if you accept the Manhattan eruv that carrying is not a problem, I’d not convinced that the fare card itself (like money) isn’t muktzeh itself and cannot be moved on Shabbos.
In any event, the Conservative takes a more liberal approach to Shabbos, to the extent of allowing one to drive on Shabbos for the purpose of going to (and coming home from) shul. The Orthodox postition is that this is forbidden. I don’t know if that factored into the author’s permission to ride on the train.
Lastly, as the rabbi himself mentioned, there is the problem of maras eyin (literally: appearence to the eye). This is where one gives the appearence that one is doing something forbidden, even if he is not. The classic example is walking into a non-kosher resturaunt for the purpose of asking for a drink of water. Onlookers will not realize that the person is going in only for water and will think that he is going in to eat at this establishment. This may then cause others to think that eating at this establishment is permitted. A similar problem may arise with regard to this train ride (assuming that riding on a train is permitted at all – the matter was left unresolved on page 2 of this thread).
My favorite translation of “maras eyin” comes from the Ethics committees which are begin more common these days in both bisiness and politics: “Appearance of impropriety”.
It’s not quite literal, but carries the idiom perfectly.