844's tender is especially picky about a curve just a few hundred feet west (behind me)--it has derailed a few times on that curve...
Somewhere, on a video I bought, there's a short segment. Showing a Big Boy crawling through a crossover. The boiler swing is truly a thrill to watch. I've been in the cab of a mallet, when it's on a sharp curve. Looks like you're heading one way, while the drive train is starting in another. Boxcab E50
Can't recall where I have it. Perhaps mine is on one of their "Best Of" series tapes. I'll need to look. Boxcab E50