Many of my students have writer's freeze - caused mainly by Miss Grundy's red pen. I've found that - by marking up errors, but not detracting from students' grades for them (at first) - there's a group sigh of relief.
A couple of students have told me that they've taken my A's and B's back to their high school English teachers (who mainly gave them D's and F's)!
I think it's important that students just write and write. It will get better over time, and our "grammar moments" smooth out some of the wrinkles. ... Or am I too easy?
I'd like to hear how others treat grammar in freshman writing.