Kim:I'm curious about this too. I can understand the surface area aspect and the slowness, but it was impressed on me in training that one should know what is above you. My instructor told a story about a guy who nearly died ascending into the tendrils of a Portugese Man 'O War. Needless to say I'm quite careful about what is above me since then. How does DIR reconcile the need to know what is above with the horizontal ascent?
By looking up.