Originally Posted by Blue Order

I think you've solved the mystery! These joggers are clearly bicycular joggers, inspired by bicycular jogging advoacte John Collander. Rather than risk death on the sidewalk due to the inadvertent drift of bicycles from the bike lane onto the sidewalk, they choose to jog in the bike lane, where there is a greater chance that they will first get and then hold the attention of bicyclists.This method reduces the likelihood of inadvertent drift due to inattentional blindness, because what is irrelevant to the bicyclist-- for example, a jogger on the sidewalk-- won't be seen by the bicyclist, and when that bicyclist takes the inevitable sex break, the bicycle may drift onto the sidewalk, thereby killing the jogger. Logic and reason tell us that the solution to this problem is for the jogger to take the bike lane long enough to get and then hold the attention of the bicyclist. The main impediment to getting joggers to abandon the sidewalks and run with the other traffic is overcoming the jogger-inferiority complex that pervades jogging today.

It's a thankless task, but if one jogger's life can be saved because of bicycular jogging, it will have been worth it.