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I don't think that's the sort of "optimization" the original poster was talking about, especially since the technique is entirely irrelevent to the benchmarks presented in the article.
Plus, what you are talking about is not so much optimization as it is getting rid of hacks that are no longer necessary because of a more permissive CPU architecture. Optimization takes general code and tunes it for a specific situation. What you are describing is actually the reverse --- taking code tuned for a specific situation (low-memory) and generalizing it.