> You wrote:
> 
> >  I would like to know more about
> > different bits used for enduance.  I use a jointed kimberwick and want to
> > know which is more harsh, this or a ported one. Do some of you prefer a
> > snaffle and why and are there snaffles that offer some control without being
> > too harsh? And what about the vosels?   
> 
> I have no experience w/ vosals, but I can comment on the other bits.
> Snaffles become more severe as they become thinner, then throw in 
> different types of joints, double joints, twisted wires, etc.  The 
> amount of control that one has using a snaffle depends on the horse's 
> and rider's training.  (Do you use seat & voice for control in 
> addition to the bit, or bit alone?  Has the horse's mouth been abused 
> in the past so that he is less sensitive?)  Straight bar snaffles 
> tend to be milder than jointed snaffles.  The straight bars put 
> pressure on the lips and evenly on the bars of the mouth.  The joint 
> allows a mild nut cracker action, thus slightly more severe.
One of the things that I always try to explain to beginning riding 
students is that "You don't control a horse with the bridle.  You control 
a horse with your weight and with your legs.  The bridle is just an 
attention getter.  You use the reins to tell the horse you are ABOUT to 
ask him to do something."
My personal favorite is to use the half-halt.  I generally will use 
just enough bit to be able to get the horse's attention.  The thought of 
"controlling" a horse with a bit strikes me as a bit (no pun intended) 
ambitious.  ANY horse can run through ANY bit.
Because of the leverage associated with a curb bit, "by its sharper 
effects it enables the rider to guide his horse with very light aids" 
making it so that the horse's attention can be gotten by just the 
slightest twitch on the reins.  I don't use curb bits until a horse is 
sufficiently responsive to a snaffle that I would never need to use more 
than the slightest twitch on a curb rein.
To quote one of my favorites, "There are numerous varieties of curb bits and 
the inventiveness of man often tries to substitute them for his lack of 
knowledge and training.  The many types of antique bits which, to a great 
extent, were instruments of torture, prove that men have always tried to 
make brutality triumph over knowledge."
Can't make any comments about hackamores or bosals as I have never used one.
In addition, even the mildest of bits can become an "instrument of 
torture" in the hands of some riders.  So it isn't so much the choice of 
bit that matters as it is the hands that hold the reins.
I have never used anything more than an egg-butt or baucher snaffle on an
endurance horse, as I have always found them perfectly adequate for
attention getting while going down the trail.  
kat
Orange County, Calif.