Also clean code usually results in compact code, which used to be effectively the same as fast code for the machines BSD was initially developed for. I wouldn'

Also clean code usually results in compact code, which used to be effectively the same as fast code for the machines BSD was initially developed for. I wouldn't be surprised if the BSD coreutils were more performant on older machines with small memory, buffers and prefetch queues (sometimes just a few bytes) than their GNU counterpart.