A bit is just a transducer – nothing more. That is, it transfers a signal from the rein (pressure) to the mouth, which becomes an electrical message to the brain to perform some type of action.
Choice of Equipment
Spurs
Gadgets in Horse Training
Training horses well is a skill that is learned over a long time. It is not possible to circumvent the process by taking short cuts. The behaviour that gadgets are intended to shape is something that good horse people learn along the way to becoming good horse people. A person cannot learn to be a talent with a horse by resorting to gadgets because they undermine the process of becoming a good horse person.