Exactly. The question was steam locomotive operating costs. Repairs in addition to the 1472 day overhaul needed to be considered. It's a convenient shorthand to lump them together, since as is often the case, other major work gets done at the time of the 1472 day overhaul. The minimum 1472 tear down, inspection and reassembly is probably the exception, rather than the rule for working narrow gauge steam. Museum locos, such as the Glenbrook, will probably reach the end of their 15 year cycle with little else to be done. I doubt that is the case for the C&TS and the D&S.
Michael Allen