> Learning to create art--drawn, written, musical--has its rules. You
> don't hold the trombone with your toes and play with your nose
> (although there's probably someone who can break even those rules and
> create something meaningful).

The problem with the word "rules" is that it can mean either "mandatory"
(as in law) or "customary."  "Rules" in art are the latter, but
many beginners assume the former when they hear the word "rule," and
thus may inappropriately demand compliance by others.

I think of art as having "conventions": "A practice or procedure widely
observed in a group; a custom".  By convention you hold the trombone
in your hands, you don't split infinitives, etc.  You should learn what
the conventions are, but not feel they are Laws, nor demand others follow
them.  In critiquing, you can, instead, offer your opinion that someone's
unconventional usage didn't work for you.

(Now, in the "mandatory" sense, computer programming has Rules.  If
you misplace a semi-colon in a program, it simply doesn't work. :-)