Note, however, that Hoare did not say, "Forget about small efficiencies all of the time." Instead, he said "about 97% of the time." This means that about 3% of the time we really should worry about small efficiencies.
As far as I knew, Hoare (implictly) did say "all of the time." The actual quotation being simply and forever:
Premature optimization is the root of all evil.
it was Knuth who paraphrased Hoare like thus:
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%.