First of all, brakes come from your seat and your 
  legs, not from the bit.  That said, the effect of the martingale is for 
  the horse to resist it when he doesn't want to be stopped, which hollows his 
  back and makes it that much more difficult to drive his rear end under him to 
  get a stop.  (As someone else already explained, very eloquently.)  
  Eventual effects of martingales are upside-down necks, hollow backs, 
  strung-out rears, and the various forms of pathology that can proceed from any 
  and all of those.  If you feel uncomfortable about stopping ability in 
  the french link, by all means go with the Kimberwick rather than the 
  martingale.  But also concentrate on the mechanics of simply setting your 
  hands and driving your horse into the stop with your seat and legs, instead of 
  using the bit as the primary stopping aid.  Think about stopping a fast 
  bicycle going downhill by only using the front brakes--disaster!!  You 
  have to stop that back end first.
   
  Heidi
  
    ----- Original Message ----- 
    
    
    Sent: Wednesday, January 16, 2002 7:34 
    PM
    Subject: RC: Running Martingales
    
    Funny we would be discussing this, because I just 
    order my first running martingale from Go The Distance as part of my new 
    “color change” for Beau.  I never used one before, but thought I would 
    try it for my racy guy, just for the heck of it.  I’ve been using a 
    french link snaffle, and decided I need more brakes because I pretty much 
    sored his mouth trying to hold him back on the last day of DVE.  I 
    purchased a kimberwicke also.  Dom thought that I should try the RM 
    with the french link first before going to the kimberwicke (without the RM 
    first), but then again, Becky Hart, my instructor when I slow down enough to 
    take a lesson, uses kimberwickes or Tteam bit and no RMs.