There are still the odd applications for which a few CPU cycles per computation can add up to a rather significant difference, but these tend to be written in C, C++, or Fortran, not Perl. Interestingly, these are largely written by people whose college diplomas have words like "physics" or "aerospace engineering" on them, and are in application domains such as numerical relativity, n-body problems where n>>106, computational fluid mechanics, 4d climate models, etc, where the problems have to be radically simplified to run on teraflop machines.
But, yes, for the vast bulk of applications, it is foolish to shave a few CPU cycles.
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