a) The whole quote is &quot;We should forget about small efficiencies, say about 97% of the time: premature optimization is the root of all evil. Yet we should not pass up our opportunities in that critical 3%&quot;<p>b) The quote isn&#x27;t talking about data structuring&#x2F;memory layout, but rather micro-optimizations of instruction sequences (removing goto statements, in the case of the original article)