Most Important Writing Lessons

I've learned a lot over the past couple years about writing.  I've almost completed a course through Long Ridge Writer's Group, I go to a couple critique forums, and most importantly I read and write a lot.  I have been writing since I was a kid, but the past two or three years are when I've really gotten into some of the more techinical details, creating stories not just as an art, but a craft.  Here are the things I think are the biggest lessons I've learned.

1.  Use adjectives and adverbs sparingly, and when you do use them, make them count.   This is the biggest one for me, and not always easy!  But I think it can make or break the story.

2.  Most dialogue can be cut.  I just picked this one up a couple weeks ago.  The article I read, on Writer's Digest, says that after you write a first draft you can probably delete half of your dialogue.  As always, I was skeptical about this, but I decided that it's true. Here is an example of how you can cut dialogue:

First Draft:
"Hi, what are you looking at?" asked Jay.
"I'm looking at something," said Timmy.
"That thing does look good today," Jay said, sitting beside Timmy.
"Yes, it does."
"Oh em gee, this thing you are looking at is really important and totally advances the plot."

Edited Version
"Hi, what are you looking at?" Jay asked, sitting beside Timmy.
"I'm looking at something," said Timmy.
"Oh em gee, this is really important and totally advances the plot."

See?

3.   The things you  learn from a critique group may be right, wrong, or subjective.  In all areas if life, not just writing, I believe it's unwise to put all of your beliefs into one group, organization, or person. And I question everything I hear.  This is the best way to receive critique advice.  And sometimes suggestions may be right for the critiquer, but not for you.  This is where doing all the reading and writing you can comes in handy, so you can decide which advice to take and which to pass on.

4.  "How to Write a Book" Books are invaluable.  For some reason I never wanted to read these when I was younger and I don't remember why, although I'm sure I was suspicious of them.  Now I know they are awesome, but I still don't recommend blindly accepting everything you read.  And if you can make it through a whole book of rules, suggestions, exceptions, and contradictions without running screaming into the night, you've found your true calling.

5.  Reading and writing are still the most important ways to learn and practice.   And once you get to a certain point, the other thing you must keep doing is submitting.  Then you will have editors/agents/publishers giving you specific details as to why they will or will not publish your work.  And just like in all the other situations, sometimes what you learn is subjective.  But when specific details are given about your writing style, not just your subject matter, they're probably right.

Did I miss anything?