Individual programmer style does matter, but languages also guide our style. I'm often asked to convert Perl scripts to Python scripts, and the originals don't

Individual programmer style does matter, but languages also guide our style. I'm often asked to convert Perl scripts to Python scripts, and the originals don't exhibit the "optional readability" you're advertising, and which Python encourages by default. An entirely different angle on all of this is that NLTK is aimed at novice programmers (linguists) as well as expert programmers (CS students). Perhaps readability is a different concept for these two user groups...