Our understanding of variation in the technology of flaked stone artefacts from mainland Southeast Asia during the terminal Pleistocene and Holocene periods has improved little since they were originally labelled “Hoabinhian” in 1932. Chronological and geographical variation has been described in terms of typological differences, but there are few anthropological explanations of lithic diversity and change. An analysis of an experimentally produced Hoabinhian assemblage is undertaken here to show which flake variables are significant indicators of assemblage reduction intensity. The results show that recording the presence of overhang removal, interior platform angle, and percentage of dorsal cortex will provide robust data on the extent of assemblage reduction. A new method for detecting assemblage variation based on the location of dorsal cortex on flakes is also presented and experimentally verified. These methods are designed to take advantage of the typical geometry and reduction patterns of Hoabinhian assemblages. These findings provide another tool to build anthropological explanations of Hoabinhian archaeology.