I've gotten fast(er).
I had not done the MUP that I initially started riding on since I started commuting a month or so ago. At that time, I was averaging 11.5 to 12mph on it over a 25 to 30 mile loop on that MUP.
I've been a little disappointed lately because I have only been averaging about 12mph on my 16 mile round trip commute and thought that wasn't much of an improvement over a month or so of riding. I have noticed that my legs seemed to not get as tired, though.
Well, I did a 28 mile loop with a 15mph wind on that MUP today and averaged 13.9mph. And my legs are incredibly fresh. And, unlike before when I rode that loop, I did not struggle around the 22 to 25 mile mark. I guess riding on the rough shoulder to work with hills and wind has made me stronger than I thought.
I am not up to the 18 plus mph averages I see some people get but I am stoked that I was able to average almost 14mph with my fully loaded MTB.