I've encountered this, Melissa. I've over-corrected grammar to the point of changing the speaker's tone, and was rightfully downgraded because of it. My feedback indicated that I changed the speaker's tone and that the transcript needed to follow the speaker's (and CW's) conversational style of grammar. I've learned to correct blatant grammar mistakes while leaving the speaker's tone intact. I just wish they had more work so I could show them that I finally got it.