I would definitely count it! I experienced a little of that this weekend. I took 4 lbs out of my weight belt to see if it would make things easier. It was great at first, but instead of testing my bouyancy at surface like i should have, i just assumed it would be fine. we had an in water surface interval for about 20 minutes and descended again...well, with less air in my tank, i couldn`t sink! someone suggested pulling myself down to about 5 or 10 feet on the buoy line and see if the air would compress enough to descend...it worked. I stayed close to the line in case something went wrong. on the ascent, i was extra careful and made sure i didn`t shoot out of the water by holding onto the line. This was a great learning experience for me. I`m an extremely new diver - and this was a great way to keep me on my toes. :) I added 2 lbs the next go around and it was perfect!