It's my first time, but I felt the deadline helped to think through my hypothesis. So regardless of NSF/HM, they helped me finally get into this issue. That's helpful even for classes I am taking now.
I think these things don't matter. Even if you truncate a citation, those are not things they use to ding you. They just would not even have time.
I've seen two winning samples from my university. One which was completed on the day and reviewed by no one (no time). Another that was heavily fine-tuned over two weeks. Radically different writing styles, and both got it. It's about what's inside. It's understandable that we will ask technical questions on this board (because I cannot help you with your biology related question as it's not my field) but let us not think that people get NSF because of the right combination of words per line, concepts per page, etc. The two examples were very different, neither used bold sub of the category heading (although they did hit those issues in the actual essay) and it seemed to not matter.
Good luck everyone. Nice to have company during this process. Now off to get blitzed. Friday night! Where's the nearest bar?