Proper bike sizing and tweeking component variables makes a big difference in the usability of the drops. I can't see a reason why it can't be comfortable for the long flat run as well as descending, and speedwork. The back shouldn't have to be bent at such an angle that it is painful to use the drop position, and if the bars are not set too low in relation to the seat, you should be able to keep a good bend in the arms, and not to overstrain the neck. It takes some work to get it right, but after you find it, it is like climbing INTO your bike rather than riding on top of it. Tinkering pays off. It also helps to get rid of the beer belly since that slapping sound may be the thighs hitting the stomach with every rotation. Alterntively, you could get smaller cranks. This may not be your situation, but last spring before dropping some weight, it sure was mine.