@rivers: Yes, being over-weighted on blue water descents makes it more challenging, but being properly weighted is only one factor that influences descent rate control. If you are wearing a thick wetsuit, you'll have to add a surprising amount of air to achieve neutral buoyancy at 100 fsw. Being able to stop immediately at any given depth is a sign that you are descending under control.
thanks for the info. as i have only dove warm water so far, i have yet to dive with anything more than a 3mm shorty. good to know when i do my aow in april, in new england.