Well we are on the "What if" trail again. One I will throw in for discusion in the USATC S160.
What if say the GWR had purchased 50 or so in 1945/6
Modified, much as the ex ROD locos had been, I see no reason why these could not have worked on main and secondry lines.
With, of course, a Copper capped Chimney.
70022