Dash is Bourne-compatible! And Bash is not installed everywhere. I can think of at least five systems i've used in the past five years that either didn't have Bash, or Bash was not the default shell, and even the path to Bash isn't the same on all systems (since it is technically an add-on). Anyway, I did not say use Bourne for more complexity, I said for more compatibility.

People are opposed to learning yet another tool. But here's the really funny thing about the "use a more robust language" argument: not only do they introduce more dependencies, they can introduce more bugs (due to increased complexity), and are almost always a maintenance headache. The one thing that's easy to maintain after 10 years is a shell script. Perl is a nightmare to maintain after 10 years (mostly due to the lack of good Perl programmers) and awk is just barely better.