The report you mention covered the competition that SR held at the time between the A340-600 and the 777-300X, the forerunner to today's 777-300ER. Indeed, with the -300X configuration Boeing was offering at the time, it would have had terrible take-off performance, and with an engine out, I could easily believe it wouldn't make it out of ZRH in one piece.
However, as I'm sure you know, that is old news. Boeing beefed up the -300X to make it the -300ER, slightly increasing the MTOW, but more importantly, going from the original spec 105K engines to the current 115K. They also added raked winglets, which further, although much less significantly, aid T.O. performance.
All that is rather beside the point, however, as this competion is between the A340-300 and the 777-200ER, which would have had no problems in the first place (at least, no more than the A330-200, which seems to have no problems negotiating ZRH). That being said, I can foresee no circumstances that would have Crossair choosing the 777 over the A340. As you said, there is no infrastructure at all to support the Boeing, as well as a lack of commonality. The only way they would go with the big twin would be if the price was too good to pass up. However, with a severe lack of demand for the A340, I doubt Boeing will be able to match Airbus' price, let alone beat it, especially in today's environment.
P.S. - Would be nice to see a 777 in Crossair's colors though - that would be a good looking bird.
Honor the warriors, not the war.