This paper presents a new approach to assessing the integrity of flaking sequences at Paleolithic sites. It combines experimental modeling with subsequent attribute analysis of the archaeological collection. The method is based on changes in the proportion of various technical spalls at different stages of core and bifacial reduction, as well as changes in the sizes of cortical flakes. This methodology was applied to reconstruct the strategy of the use of lithic raw material by late Neanderthals of the Altai, on the basis of the Chagyrskaya Cave assemblage. The study has shown that the most common method, using the proportion of cortical spalls, is not universal, and has limitations due to the structure of lithic industry and the specificity of raw material. When pebbles and boulders of various sizes are used, as in the assemblage from layer 6c/2 of Chagyrskaya Cave, a high proportion of cortical spalls can result from the production of bifacial tools at the site. The study demonstrates that the first stage in core reduction occurred outside the cave. The high proportion of cortical spalls in the assemblage is due to the fact that bifaces were manufactured in situ, whereas tools on cortical flakes and cortical tool blanks had been transported to the site. The study reveals a connection of various technical spalls with stages in core and biface flaking sequences, and their number is evaluated in the cases of complete versus reduced flaking cycles.