Norvig on Adaptive Software
norvig.com
norvig.com
It seems like there are a lot of software engineers that try to achieve the absolute perfect design, just like there are many who don't try at all. As with anything in life, extremes are rarely optimal.
It is advantageous for your source code to be succinct and rewritable, but not for it to adapt its own resource usage patterns. The adaptations could cause cascading performance problems. Just do the simplest design that gets the job done, profile, then use the feedback to optimize your algorithms. Such is software.