Rolling backwards while pedaling forward on a Freecoaster Can anyone tell me what happens when rolling backwards while pedaling forward
on a freecoaster bike? I mean does it gradually slow it down, or does it come
to an abrupt hault? I have not tried it yet.
I think there is some confusion about the difference between a Freecoaster hub, a Freewheeling hub, and a Coaster brake hub. So briefly:


A freewheel hub is by far the most abundant and utilized piece of bicycling technology and relies on a ratchet and pawl mechanism (or similar) to engage the drivetrain while pedaling forward, but allows coasting when not pedaling. Any freewheel or cassette hub uses this technology.
A coaster brake is a type of brake that is built into the hub shell that turns backward pedal force into braking force. 
A Freecoaster hub uses a clutch mechanism to engage the hub shell while pedaling forward, but disengages the hub while pedaling or coasting backward. This allows you to coast backwards without having to move your pedals. They are totally silent because there are no pawls!



Above is a hastily drawn sketch of a freecoaster hub. There are no pawls...instead is a cone shaped clutch which is threaded onto the driver body which extends over the axle. The driver cog on the left is supported on the axle by bearings on either side (there are also lots of other bits and pieces, but these are the general parts.) When pedaled forward the driver threads through the clutch and pulls it into the wedged surface of the hub. The friction between the hub and the clutch is what drives you forward. When you change directions (or pedal backwards) the driver threads the clutch to a backstop which adjusts the play from freecoasting to pedaling forward.

If you were to pedal forwards while coasting backwards, your pedal force would engage the clutch into the hub shell. -- As @Daniel R Hicks pointed out, this is pretty much the same mechanism that a coaster brake utilizes except in reverse. Pedaling forward ought to engage the clutch and slow you down. --

However...I'm not sure that I recommend that you do this because neither the clutch surface nor the hub shell are designed for slowing, only for engaging. (If anybody has more info on the actual construction of the hub shell...whether there is a steel insert to bear against and provide braking support, or whether the driver and hub shell are forward motion only, please edit away.)

Here is a fantastic video about freecoaster anatomy.