I have a favorite route that I run about once a week.  It takes me downtown Martinez where I loop once around the county courthouse and then retrace my route on the opposite side of the road.  In all it is about 4.75 miles.  I don't often record my times or mileage being a very practical optimist.  If I don't know - I can't be disappointed.
Last week I recorded my route on a new Android GPS tracking app - Endomondo.  (Seems to refer to "endorphins")  I ran what I thought was a fast pace but looked at the statistics and was chagrined to see an 8+ min / mile average speed.  I lived with that assumption for a week. 
Motivated, I tracked my route and time on the same path a week later.  This time I allowed the "virtual coach" to shout over the music and give me my split times through my ear buds.  I ran fast and cleared the first mile in 7 minutes 2 seconds.  I lost 20 seconds on the second mile, but it finished my first climb, so a small drop was to be expected. 
The wheels started to come off the wagon in mile 3.  7 minutes 53 seconds, and then mile 4 was 7 minutes 59 seconds.  Run... Faster... Run... Faster
I lengthened my stride for the home stretch, fighting a stitch and a sour stomach.  I crossed the road at rush hour - sans crosswalk - timing it well enough to not be flattened or scorned.  Right turn into my neighborhood and a left down my street.  Stop.  36 minutes 21 Seconds.
Average speed 7:36 per mile.  Smile.
Then I reviewed the history to make the comparison.  Last week 36 minutes 7 seconds.  Wait a minute.  I had a better time last week?  Evidently.
I'm not sure what state of mind I was in at the finish a week ago, but I obviously misread the data. 
I had been motivated by a mistake.  Frown.
So, I actually did worse?  Stink.
Next week...