Aaargh (an ode to dodgy web developers)

How many times do you have to tell someone that it is not OK to put comments in javascript by using HTML-style tags, before you're legally allowed to break their fingers?

eg.

<script language="javascript">
a_function() {
  <!-- preload car rollovers
  foo = bar
}

(yes, I know it's missing the type attribute, too! :/ )

Why do I ask?
Because it's been five days of telling them three times a day, and I'm beginning to wonder if there's a claw hammer nearby..