Hey, Iwantcurlyhair (love that name!) the best I can describe my experience with the recent blunt cut was that my hair had no shape above then ends. I just kind of hung there. Which honestly wasn't so bad in the winter, because I like to have my hair as close to wavy as I can get it, since there is less humidity in the winter. I'd rinse right side up and comb gel through my hair and air dry so it lay flat. The problem came about when I tried to style my hair the CG way, rinsing upside down, scrunching in gel, diffusing a little. Since it was straight across, all the volume was concentrated towards the bottom of my hair. I'll post some pics to illustrate:
(You can click on them for a larger version)
These two are the sorta wavy styling, no-humidity, dry winter hair:
This is when I did the rinse upside down, scrunch & diffuse thing:
Now, some people might like that big hair look, and the shape and all, but I just didn't dig the way it was so full on the bottom. So I kept doing my hair the wavy way, until all of a sudden we had one humid, summer-like day here in New York City and I totally freaked out. My hair gets very frizzy and big in the humidity. So I imagined a summer of crazy big on the bottom, flat on the top triangle hair. So I went back to the salon and shelled out another $60 or whatever it was and got it fixed.
Just for a comparison, here is a picture of my hair styled the same way as the above big haired pic, but with layers (back when I could actually afford to go to Devachan!):
Granted, it's shorter in the second picture, but the fullness isn't concentrated towards the bottom, it's sort of tapered at the ends.
Now to answer your other question, I always clip the roots, whether I do the rinse upside down scrunch thing or the comb the gel through wavy thing. Otherwise I would have no volume except down at ends of my hair. I've got fine hair that's not really curly up by the roots, so I have to give it a little helping hand.
(edited to fix broken link)