Of course it’s about horsepower, no question. Not saying the steam ship are faster in theory.
I was saying maybe it was capital cost vs operational cost. In other words maybe the steam plant had more hp per dollar in capital cost. But operational costs were higher because of fuel consumption.
That’s what the analogy of Tote ships to the 70’s muscle cars implies. It was cheap horsepower.
Assuming steam is better $ per HP than spending just a little more on a bigger steam plant to get more margin to meet specs makes more sense than having to make the big step from a 7 cylinder to an 8. The guys building diesel ships are going to use a sharper pencil to calculate HP required.