The impression of this fic by brave souls reading it on DW seems to be that the author has assembled some grasp of the factual historical narrative, whilst entirely missing the broader picture - sort of ironically, preventing their having qualms.
The glory of the summary is that it warns a person like me, who knows only the barest historical outline, but a lot of the context, that this is going to bizarre places. The idea of the Black and Tans as "special forces sent over to keep the peace" is sublime.

TJitC crossovers is the gift that's going to keep giving for some time. Susan Layton definitely thinks the world should be the Chalet School, and clearly this is actually what happened in the (real) lost CS manuscript, Two Chalet Girls in India.