That is not the problem. I am just saying if someone is averaging 15, for whatever reason, expecting a 4 MPH jump in a year or two may take some creative logging. I run my average from door to door. I ride to the start of the ride after stretching and spin till my HR gets to about 122. I don't reset the computer when I get to the meeting place for the group rides and I don't reset it during the cooldown spin heading for home. In a TT or a road race I can hold between 22 to 25 for most of the race. But the recovery ride the next day gets averaged in as well. After all I am on the bike and I am riding so why not add it? A ride to the store may be only 12 MPH but it is a ride and it goes in the pot. 22 miles on the MTB gets tossed in as well. If I am riding it gets logged and averaged. My best 100 miles was at 16.8 and my worst was at 13.6. But like I said that includes stop lights, stop signs and nature breaks.