Can I open a route I created in Google Maps in Navigation? I'd love to be able to open that map on my phone in such a way that I can get turn-by-turn navigation, like what is available in the Navigation app.

However, despite my experiments, this seems to be impossible. I would have thought Navigation and Maps would be based on the same formats and code, but there appears to be a wall between them.

Is there any way I can create, edit, and save a map on the Desktop, and then have it viewable on my phone for turn-by-turn navigation?

The key is that I use this for biking, and I can not see my phone while I'm riding. So I want to have an earpiece and be able to hear instructions for turns.
Google Maps for Android does have a bicycle option.  You just have to select it from the drop down menu.