Otto had it easy.....Less traffic, more trains to shoot, and less railfans to get in the way!!!
Colorado particularly was a railfan photographers paradise and luckily he took advantage of it before it was all gone.
He did seem to maximize his time, which of course is just as important as having knowledge of the subject. We used to joke that being a steam railfan photographer required many talents, including: good photographic skills, map-reading,
rally driving, train schedules, photo locations, weather observation, car mechanic, and a bunch of other stuff. Then there is another factor....LUCK. If you do all of the above well then you can make some of your own luck.
Its nice he was around to render so many historic images so that another generation could see what we missed.
Greg Scholl