bit twiddling: n. 1. (pejorative) An exercise in tuning (see {tune}) in which incredible amounts of time and effort go to produce little noticeable improvement,

:bit twiddling: n. 1. (pejorative) An exercise in tuning (see
{tune}) in which incredible amounts of time and effort go to
produce little noticeable improvement, often with the result that
the code becomes incomprehensible. 2. Aimless small
modification to a program, esp. for some pointless goal.
3. Approx. syn. for {bit bashing}; esp. used for the act of
frobbing the device control register of a peripheral in an attempt
to get it back to a known state.
-- The AI Hackers Dictionary