The bug in this case was in fact one which could readily have been caught by unit tests, no? I don't see why demanding test coverage is intellectually incoheren

The bug in this case was in fact one which could readily have been caught by unit tests, no? I don't see why demanding test coverage is intellectually incoherent. Arguably it's somewhat half-assed, but not incoherent. Why shouldn't systems developers at least pick up the low-hanging fruit of tests? The effort isn't too monumental for Rails.