Paul on the Road to Assos (Acts 20)

I like the book of Acts and dabble in Bible geography so I enjoyed this post by Carl Rasmussen on Paul's trip to Assos from Troas and his companions trip by sea to Assos (Acts 20:13–14). So good so far. But trying to determine why two different routes were taken is difficult because the text simply does not tell us. But Mark Wilson offers some suggestions that are then challenged and defended in the comments. Good stuff.