During the Cold War several countries, including Sweden, Finland and the Soviet Union, kept SSRs and the United Kingdom is reported to have done so, albeit without evidence.
[1][2][3][4][5] Following the complete withdrawal of mainline steam traction in 1968, the myth persisted for decades that a reserve of locomotives had been retained for such a strategic purpose.
Rather than applying Hanlon's razor to this evident wastefulness, the assumption was that there must have been some other secret justification to constructing a fleet of new, capable and standardised locomotives.
The Austerities were solidly constructed, reliable and easy to maintain; despite slow speed and short range, they were also powerful in terms of tractive effort.
They were the last standard gauge steam locomotives to be constructed in the UK in the 20th Century, and were in a good condition, especially regarding their projected boiler life remaining.