Unfortunately Mr. Staghurst's comments betray his lack of knowledge, not only of what is possible with steam traction but also of what has already been achieved. Consider the following.

The above figures, which are amply supported by other data, show eloquently enough that the calculated power capacity of the 5AT is perfectly realistic, and I regard achieving it as a formality (and surpassing it a probability) - even on this planet! Likewise all factors concerning thermal efficiency, except the target combustion efficiency at maximum evaporation, which I have acknowledged will be a difficult problem. But that does not mean impossible, simply that very good engineering will be required to achieve it.