Arabian "S" bit

["Glenn Foster" <gfoste19@idt.net>]

<<
There is a wonderful hackamore type that is perfect for the endurance or
trail
rider.  It's called the Arabian S bit.   ...
>>

Hey, thats what I'm using with my new little guy!  I picked it cause that's
what the tack
shop had with short shanks the morning I decided to upgrade from a lead
rope
on the halter.  Can you tell me what the "S" shape of the shanks is for ? 
Also I cut
off the wire between the shanks (looked like it might cut a chin on a bad
day), and replaced
it with a shoestring.  Is there anything "scientific" about the "S" curves
and having the 
shanks fastened together ?

Glenn