There are two logical routes that I can pick from. The side streets are very narrow and people run stop signs like crazy - cars and peds. So I want the widest, most heavily trafficked routes to discourage cross traffic. Decatur is near the river so not much traffic can cross or come from the left. Seems counter-intuitive, but all my cycling buds agree too. Decatur Street gives you the best sight lines and least cross traffic. Plus, it has a nice double yellow "bike lane" right up the middle!