S3X neutral gear?
 

I'm a little confused about this. I've heard that there's a "neutral" in between low and middle gear. Is this something that you can hold in place if you were going down a hill and wanted to coast?

Not without damaging your hub.

There is a spot between first and second in which the hub doesn't engage and does allow you to coast. When I first got my hub, there was a defect in the shifter that allowed the hub to pop out of first into "neutral". This happened a couple of times and trashed the internals of the hub. Luckily, Sturmey Archer were very good about sending me a new shifter and hub guts.

In short, don't get any ideas about being able to shift between fixed and free on the fly. Better to just get a "normal" bike and pedal all the time, until you don't want to.

There are three gears: direct, high and low.

Hope this helps.

The Sturmey-Archer S3X hub is an "all down" design and has three ratios: 1:0.625, 1:0.75, 1:1; i.e., low, medium, and direct.