Recumbent vs DF
We have gotten together more than once with my cousins and ridden the Katy Trail more than once. With the trail being a fine packed gravel your speed does not go much over 12 mph if you want to keep a comfortable pace. That is regardless of what type of bike is ridden.
The first time we rode the trail it was on DF's. A couple of years later we rode it again with recumbents. What we found out was that the speed was about the same between the DF's and the 'bents. The comfort factor on the recumbents over a long distance is what really makes a difference. We were able to go a longer distance in a day's time with the 'bents because of that. I was riding a Sun EZ-1 on the second trip; a Raleigh Grand Prix on the first. The Sun has a top speed of 15mph for me with the gearing on it. What does help greatly are high pressure tires on a recumbent.
With recumbents (at least with the Sun's) with the extra seat padding you really don't need the padded shorts. Moisture wicking fabric is the main thing.
PhilWinIL