Join Date: Sep 2007
Location: Washington State
Just as a note, it is my personal opinion that the bit should never be relied upon as your only stopping device. Asking a horse to stop is not as simple as pulling back on the reins. It also involves your body position.
I have also never heard of the middle piece putting more pressure on the tongue and therefore being better... but I cannot claim that it is entirely incorrect. I think that the contouring of the linked bit is meant to evenly distribute the pressure, though... not create a pressure point.
Finally, just because a bit is gentler does not mean that you are giving up the ability to control your horse in emergency situations. In fact, a horse that is not uncomfortable and tense is therefore light and responsive is more likely to stop or turn sharply.
Sometimes, if your horse has been trained poorly they may have learned to "lean" into the reins or keep their neck and jaw rigid, both making it difficult to direct or stop them. Because they feel restrained or are made uncomfortable by their bits and methods of being ridden, they may become stubborn or flighty. In these situations it is sometimes appropriate to use a harsher bit in order to get your message across that you ride with light hands and an easy seat. Ultimately it is my personal opinion that the rider should always progress toward a softer rein and gentler bit. In other circumstances it is better to immediately switch the horse to a gentler bit or even a hackamore rather than a harsher bit. The most important thing is to find an instructor you feel that you can trust to guide you through these processes.
I will admit that much of this is my very personal opinion and some people will not agree with my views. Every rider is different, and justifiably so -- every horse is different. Nothing can be said with absolute certainty.