Those are very interesting articles!
Being an engineer, I have an interest in these kind of things, but its not always easy to convert whats in words to what you do every day out on the railroad, but its interesting to me, because I understand whats going on, but I dont' always know the reasons or the words or laws of physics
Im not the sharpest spike in the tie........
There is one factor that is often overlooked with regard to train/locomotive performance.
That can be a HUGE factor. Just like a professional race car driver could make your Ford Taurus do things you would NEVER imagine, and drive it faster and harder than you ever imagined or ever could, the same applies to Engineers. Everyone drives their automobiles differently, and engineers run differently. And im sure it was even more of a factor back in steam days.
Some engineers can simply get more out of a loco than someone else. I once took a train of loaded stone hoppers over a stretch of track with one locomotive that the engineer who got the job the night before stalled with 3 locos (the closest my commuter operation will come to running a "real train" as some freight guys like to say....). It took a lot of work to get moving, but I was able to get it to move and made it on our way. The Conductor was the same as the night before with the other engineer and he was shocked. Its not anything special, but sometimes you just can't give it gas and go. It takes a little effort to get to move. Why could I get the train to move with a 3000 HP pax geared Geep, while he couldnt' do the same thing with 9000 HP 3 passenger geared Geeps....I honestly don't have any idea how he managed to stall it with that much power, but if you knew this guy......but I bet it had something to do with just throttling out (or not checking the other units to see if they were MU'ed properly...) and hes probably lucky he didnt' rip out a drawbar....the hoppers we use are about 60 years old..haha. BTW, a passenger geared Geep (meaning 103mph I dont' remember the gear ratio off hand) cannot pull for anything.....a single freight geared GP40 would be fine, as it has the power down low, but the passenger gearing means these things are just terrible at anything but passenger trains.
Im not saying im the best guy out there, or the worst guy, just giving a example of how by all measures, 3 Locos should have been more than adequate, and it wasn't for one guy, while I was able to do it with 1.
But at the same time, never underestimate the power of a quit
"We don't have time to wait for another loco to come....this is fine!"