Yeah, I've also seen several academic papers on performance or "optimization" of existing algorithms which just demonstrate a complete lack of knowledge about how those algorithms are implemented in practice.

For example, there was a paper explaining how you could optimize the GJK algorithm by reducing the number of distance checks required, and in turn the number of square-roots... Despite the fact that everyone (including the authors of the original GJK algorithm) knows that you don't actually need to do a square-root to compare distances...