How can you be sure?
Just take a look at the standards package.. How is it that people who write in all different sizes of writing, with VARYING abilities at being succinct all hit both the band 5/6 mark and the 7/8 page mark simultaneously?
When the... Marker flips through the pages and notices you've got the whole booklet filled, he gets a warm and fuzzy feeling inside. From then on, after this realization of 7~ pages, your essay has favor.
Now if you go ahead and write random things in those 7 pages, youl'l quickly lose that favor. But say, you compared the essays of two students, one who's written 6 pages, the other who's covered the EXACT same content in 8 pages, with a little more long winded response.
I can gaurentee you the 8 page guy will > the 6 page guy, even if those 2 pages were filled with nothing more than extra "ands" and sophism.