A truly anatomical saddle that distributes your body weight over the whole seat might really help. Some riders try to alleviate this problem by tilting the nose of the saddle down, but this only results in a tendency to slide off the saddle and to strain your shoulder and arm muscles. Secondly, and to a much lesser degree, you tend to get a sore neck the first few times you ride, the discomfort lessens with time and can be minimized with stretching and massage. These draw backs are minimal because you don't have to ride the forward position daily to go fast on it. Narrowly spaced elbow pads.
Narrow elbows are an essential detail of an aero position.
However, the magnitude of improvement is much less than what is achieved by adopting a horizontal torso position. Research conducted by Boone Lennon has shown that subtle changes in elbow width and aero bar angle may have significant effects on drag. This research was performed on traditional geometry bikes, with the torso adopting the characteristic cupped shape, and probably illustrates the need to block air flow out of the torso area. More recent data on riders in a horizontal torso position shows much less effect from these variables. I do not believe these two findings are contradictory, rather, they indicate that once the torso is horizontal there is little you can do to improve or impair aerodynamic drag.