well if he had over 152 horses and no crates he could have caught you (he would run about 89 m/m.) You are running 49m/s??? You don't have any goods??? Wonder why he attacked you??? or do you have horses to help???
But I think, from what I've been told, that he probably locked on you and let the program calculate the proper angle to chase you and cut your path. Again, I've been told you can do this and also that you have to be pretty much right on top of somebody to attack them. I've never experienced it myself so I could be talking rubbish