I try not to pay too much attention to the minute details of what my Garmin reports. I've never changed the settings; yet, it seldom reports the same mileage on routes that I've ridden hundreds of times. I think of the data it creates as an "overview" of the rides.
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A conclusion is the place where you got tired of thinking. - S. Wright
Favorite rides in the stable: Indy Fab CJ Ti - Colnago MXL - S-Works Roubaix - Habanero Team Issue - Jamis Eclipse carbon/831