Apologies for driftng off topic. When I was in Hong Kong tower we had at least 3 separate instances whereby aircraft that had been cleared for take-off on RWY 07L (it was early morning 1am to 3ish), lined up on TWY ALPHA parallel to RWY 07L. A Finnair A340, A Philippines A330 and a Hong Kong Airlines B738 and all three lined up on the taxyway "ALPHA" and commenced their take-off rolls. I know because I was the one that desperately instructed the PAL aircraft to "Stop immediately" as there was a 10 tonne sweeper operating on TWY ALPHA about 1500 meters down the TWY. Because these were departures there was no facility for immediately reporting and taking action regarding these transgressions. I could merely log the circumstances for management to action the next day. I guess the moral of the story is that there are a number of participants that keep the holes in the Swiss cheese from lining up so .... be careful, be alert, be suspicious (smell the rat) and respect SOP's.