that's just a common knowledge when you follow the war daily for years. vast majority of the frontline is 10 troops/km beating meat across the field of same 10 enemy troops. the whole kursk incursion was 2k. the whole kharkov barriier zone is 10k. largest recorded casualties in one assault are ~30. bakhmut was the largest meatgrinder by far, it was the only hot spot on the whole front for a year, the first time convicts were used so lots of them available - and it was just 20k casualties over the whole operation.
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