"The carabiner wrap is probably the world's most used rappel method.  Thousands of soldiers have survived this method's drawbacks.  A few have not.  This rappelling system uses a carabiner in a manner for which it was never intended....
This is a fixed friction method and once over the edge it cannot be changed and often rotates the rappeller and kinks the rope causing laid rope to hockle."    

Again, without adjusting the friction I don't see how it would be possible to rappel a long rope.