We previously covered "the secret" to hatching eggs in Pokemon Go, namely that the game uses periodic GPS tracking to calculate distances in the game. Instead of using a phone's pedometer (which measures steps) or continuously tracking your distance via GPS, Pokemon Go "cheats" by periodically pinging your phone and calculating your distance walked from the last time it checked your location. Think of Pokemon Go's tracking as basically a game of connect the dots.
However, Pokemon Go's system might have a few more flaws than thought. A recent article on Kotaku detailed how Pokemon Go seems to wildly miscalculate a player's distance traveled while running, resulting in the game only counting a fraction of the distance traveled. The article's writer, Stephen Totilo, posits a few possibilities for the wild inaccuracies but can't really come up with a satisfactory answer other than that maybe Pokemon Go doesn't work the way we originally thought.
Totilo's article echoes the complaints of many other runners who have also noticed big inaccuracies between how far Pokemon Go thinks they ran and their actual distances We know that Pokemon Go only tracks distance if you're traveling under a certain speed, which was widely assumed to be around 15 miles per hour (which is around the top speed of the average runner). But as more runners report inaccurate speeds, could it be that Pokemon Go's "maximum speed" is set lower than previously thought?
As someone who has driven backroads at a slow speed to help my eggs hatch a little faster, it's clear that Pokemon Go at least sometimes gives players credits while moving faster than a walking pace. But as most players have noticed that Pokemon Go only accurately tracks distance while walking in a straight line, it seems that the best way to hatch eggs in Pokemon Go is to move at a light jogging speed, at best.