David: You're right, it is water. I read the article but didn't bother watching the video, as I usually skip them to save time. I actually prefer reading my news...but sometimes one does miss things that aren't put in print.
Leggy: Even the best track isn't enough if the layout isn't stable. Wonder what the "earthquakes" would register as when the average layout is bumped? Anyone for making a scale seismograph? And, yes, I've had trains blown of the track before. My Loudwater River Bridge used to cross a window in my bedroom. When the window was open a gust of wind at just the wrong time could derail the train. As it was inspired by the MILW's Beverly Bridge, which had the same problem, it was sort of prototypical...