There are many great reasons to go bit-less, like:
1. You can.
2. It gives you more options for how to communicate with your horse.
3. There are so many options, there is no need to give up a nuanced feel.
And a few to consider as to why not (or, not exclusively):
1. Many bit-less options put far more pressure, physically and psychologically, on the horse than a basic bit does.
2. Many shows do not allow bit-less bridles. In some cases, this is just due to tradition and can be challenged. In others, it is because the show staff are well aware of #1.
3. If for any reason that horse must be sold, it is far easier for a horse that is comfortable in a bit to find and keep a good home. Even if you expect to own the horse for their entire life, invest in their future and make sure that they understand a basic bit.
There is no one magic piece of tack, and that especially applies to any item we use to exert pressure on the horse’s head. Every horse is an individual in conformation, temperament, and training, and so is every rider or handler on the other end of the line. I feel that this is, perhaps, an overly obvious statement, but ads still abound for bits and bit-less rigs guaranteed to “fix any horse” or “be more humane.” When choosing headgear (or any other piece of equipment), consider what pressures it exerts on the individual horse.
Common areas of pressure:
Bars The naturally toothless portion of the lower jaw.
Lips The corners of the mouth are incredibly sensitive. As such, this can be the gentlest or the cruelest type of pressure. Any direct rein use with a bit will put pressure on the lips. Gag bits will exaggerate this effect.
Tongue Most bits will apply some pressure to the tongue, but it should not be the only or sustained point of contact.
Side of muzzle Usually the easiest pressure to introduce to a young or headshy horse, which is why full-cheek and d-ring snaffle bits, and side-pull and bosal bit-less options, are so popular for starting horses.
Bridge of nose Pressure varies considerably based on placement and material.
Curb Under the chin. This pressure can be very subtle, or vice like. As an indirect pressure, it is not immediately “horse logical,” and should be introduced systematically to a horse that is already well accustomed to a rider and more direct pressures.
Poll Top of the head. This can be a very nuanced addition to horse/rider communication, but it can also be very frightening to the horse. Many “humane” rigs, including the Dr. Cook’s Bit-less Bridle, have an incredible amount of poll pressure and can cause horses to panic.
Palette Either accidentally, from a single-jointed mouth piece with both reins used strongly, or purposefully from a ported mouthpiece. A ported mouthpiece is not necessarily a more severe bit, but there are many very severe ported bits. Ports often make more “sense” to a green horse than the curb pressure they generally come with, but should still be introduced slowly and systematically. In addition, while all tack should be fitted to the individual horse, it is absolutely critical with ports. Depending on each horses mouth shape, the same ported bit can be very mild or immediately painful. Ported bits also tend to be heavier, which should be kept in mind when fitting (this is also why you always find dozens of old aluminum curbs at auctions– it isn’t just because the metal was cheap, but also because it was light).
I am often asked about bits I love or hate, so for articles to follow I will tag them:
Green: Suitable for everyday use, green horses, and green riders. Generally these are smooth mouth snaffles and direct pull bit-less options.
Yellow: Suitable for everyday use and green riders, but requires some training for the horse. Most simple curbs, including bit-less options.
Orange: Not suitable for everyday use, probably not something a beginner should use, and requires training for the horse. This is a pretty large category, ranging from double bridles to gag hacks to spade bits.