I considered going for a Entry Plus but worried about the fact that if they're reading your story with a much more critical eye (in order to provide constructive feedback) then it's going to take away from their enjoyment and get you a lower score, no?
Nah. We don't even know which have entry plus the first time through reading them:
Read 1700 stories.
Bring the list down to 150 stories.
Bring the list down to 15 stories.
Choose 6 stories.
Entry Plus. This is why entry plus isn't being send out early. As you say - it would ruin our enjoyment of your stories should we study them closely. We need to read them as readers, not as teachers / markers
