I'd be fine with granting this an exception, if we limited the scope of the change allowed. In particular, rather than directly editing Freemedia-form.html and adding/removing dozends of lines each time, a 1-line change in init.pp could accomplish the same thing, publishing either the 'open' or 'closed' page as necessary. Then such a change hitting the puppet master tree would be very limited and clearly couldn't break other things.
You are right!!!!!! It's my fault that I never thought about it. Thanks for pointing.