Like, for instance, the reason why Andre named his first 3 activities Student 1, Student 2, and Student 3. I finished Student 1 with no problems at all, but I was a bit confused as to why everyone was saying how responsive the Alcos were. I thought they were pretty sluggish, myself. I figured I'd just been playing with locos that didn't have realistic physics, and plowed ahead. But when it wasn't any challenge at all to bring the train down the hill into Junction, I started to wonder. It really made me think when I uncoupled the train at Seligman and moved to tie up on the engine track. Those big guys really didn't seem to be very smooth.
About an hour later, it finally occurred to me that I'd probably left the loco brakes set! Sure enough, as I started Student 2, I checked the starting loco brake position and there it was - 100% Doh!
So this student has learned something! I periodically need a smack upside the head to get me to pay attention to details, and thankfully, I'm often the one who gets to administer the smack!
But I also learned a bit more - those Alcos do indeed have some pulling power! I didn't have any trouble making Tunnel or Seligman Hills, even with the loco brake set at 100%.