First off, congrats serpent333 for the terrific score and improvement in only a month! Your debrief will hopefully help some other people looking to make similar improvements in their scores.
I can't say for sure whether you can get a 5.5+ with only two body paragraphs on the AWA, in theory yes if they're particularly well supported. If you end up with something like a 5, I don't think it's a big concern, especially with a 700+ GMAT score. I'd only be worried if it was below a 4, which is highly unlikely with such a strong GMAT score as it's basically the same verbal concepts tested in long-answer form. Please keep us advised on your official AWA score when it comes in the mail.
Also, the GMAT exam is entirely designed to reward those who are fresh and well rested. It's an exam of relatively simple concepts asked in confusing ways to see who can break through the clutter and the fluff. On top of that, it's like 4 hours long, so if you were feeling fresh in hour one you may not be so into it by hour four. Anything less than total mental focus can only drop your score. I'm not quite seeing the "being physically in shape" aspect tring375 mentioned, unless you just mean sleeping well and therefore being rested. The GMAT doesn't give extra points for having abs or big arms, although it may be worth doing an experiment in that regard!
Hope this helps!
-Ron