Yes, to avoid traffic you can make the right turn onto East Rd. that takes you to the Fort Baker area and then continue on Conzelman (which is closed to cars once you cross under the bridge and start to climb) up to the west side of the bridge. That way you're only on the busy part of Alexander for a short distance. But you do have to do a little more climbing on this route than if you stay on the main road up to the bridge path.