To Assess or Not to Assess

When writing do you just write or do you write a little then read it and correct every little thing that is wrong? Do you worry about being correct when you write or do you just write?

I believe that when you write you just have to get everything out and then just go back and correct mistakes. Better yet, why don't you just write and then have someone read and correct your work for you? I think you just have to use these questions when writing. From the Norton Field Guide, What works? What still needs work? Where do you need to say more (or less)?  If you use these questions writing should not be a problem. You also have to know who your audience is because if it is your friends you can use simple things to explain because they know who you are. When writing to other students or teachers you have to explain everything in full detail so they understand what you are saying.