Fly tying rules: in or out?

2 day ago, I posted a new pattern. Here is the pattern link http://
www.versacorp.cn/picImg/Adams-Big.jpg . I have got some feedback about
my pattern.

----The fly is not tied true to the accepted pattern, the proportions
are wrong, and it should be tied in sizes 10 to 20. Other than that,
it's perfect.

----Often it's more important that -I- can see the fly than to make an
exact match - the fish don't mind.

I have a question to ask whether we should strictly follow the tying
rules or just use your imagination to tie what you want to tie and
have fun. You know, even some patterns I have seen do not follow the
rules but they still could catch fish. So what are your comments?