It's not just bike lanes, it's more off-road paths, more signage, etc. You're right about those four-ways--they only work if you know and trust the "normal" traffic flow.
Although if you read the comments on this blog post, you'd assume someone had suggested we outlaw all forms of automobiles and force everyone to ride a bicycle everywhere. Nutso.
http://greeninc.blogs.nytimes.com/2010/03/26/transportation-department-embraces-bikes-and-business-groups-cry-foul/