Now, with those caveats out of the way, the question of whether or not to use gadgets, and how to use them if you do, came up in the comments yesterday, and I have enough to say about that topic that I decided to do a post rather than respond there. I used to use gadgets - lots of them - any new bit or device that came out and I was on it - I've used them all. I don't use any now, ever, although someday there'll probably be a case where I do for a specific reason to prove me wrong. The only equipment I use is a bridle without a noseband and some sort of snaffle bit with a smooth mouthpiece, a web halter (occasionally a rope halter, but rarely) with a cotton lead rope, a saddle (that fits) and occasionally long lines (almost always without a surcingle). That's it - no spurs, martingales, draw reins, strong bits, flash nosebands, crops or whips (although occasionally a crop used as a secondary aid on my leg - not the horse - can be helpful), no bitting rigs or anything else. (Parenthetically, it's possible to classify all tack, and particularly bits, but also bitless bridles, as gadgets, but let's classify basic tack as "not gadgets" for purposes of this discussion.)
I'm not just a refusenik - there's actually some thought behind this. My objective is for the horse to be able to move, by free choice, in a way that is soft and relaxed and capable - just as it would in the pasture without a rider. This means that what the horse does has to be by choice and not constraint. I also want to know what the horse is thinking and feeling - the horse must be able to express itself and the conversation has to be two-way. So this is the first reason I don't use gadgets - I think they tell the horse what to do rather than ask the horse so the horse can figure it out. The analogy is, when you're teaching someone to add, one way to do it is to give them the answer and drill them in the answer, so they learn that 2+2=4. The other way is to teach the person how to add, which will not only allow them to figure out that 2+2=4, but also to figure out lots of related things - and I'll bet they remember this better than a drilled answer. (I can't take credit for this analogy - it comes from Mark Rashid.) Using gadgets usually just gives the horse the answer. I believe it's a lot more powerful to help the horse figure out how to respond to your ask, on its own - the learning is more powerful and generalizes better to other situations.
The second reason I don't use gadgets any more is I think using them is often a slippery slope, for riders and trainers. It's very easy to become dependent on them, use them too much and develop a way of riding that requires them. There was an interesting example at a barn where I used to board. There was a trainer there who had some nice horses. But every horse she had, hers or a boarder's, was lunged all the time in a bitting rig. Every horse was ridden in draw reins or side reins or a neck stretcher in a tight position. Even when they were jumped, they were in side or draw reins - and that's an ugly thing to see - the horses would try to jump and hit themselves in the mouth, refuse and be punished for it. Those horses never got a release or a break, and they were crazy. One day the trainer rode one of her nice warmbloods without the devices, and he went nuts, flipped out and threw her - she broke her ankle. The horses had no idea how to carry a rider without leaning on the devices - without them the trainer and the horses were both lost. Now I'm not saying that all people who use devices go to this extreme. But many riders and trainers use gadgets too much and for the wrong reasons, in my opinion. Gadgets and devices are often used as shortcuts instead of real training, and they're used as crutches. They're also used because that's the fashion in a particular discipline. They're often used to more quickly produce a "headset" or a "frame" that's pure illusion, without any real softness at all.
The third reason I don't use gadgets, particularly those like drawreins that apply a leverage effect to the bit, is I don't think I'm a good enough rider, and I don't think I'll ever be. The mouth is one of the most delicate parts of the horse's body, and a misused bit can cause severe pain and even permanent physical and mental damage. Using leverage on the bit amplifies this risk, and the gadget just becomes a means of coercion, and if misused enough, a way to produce fear and tension. Now I've been riding for many years, and I won't use these gadgets for fear that I might, even unintentionally, do physical or mental harm to the horse. I believe many people who use these gadgets aren't better with their hands than I am, and I would include many people who purport to be trainers in this group. Your hands better be darn good before you consider using a leverage device on the bit, in my opinion.
Now those are just my opinions. If you do use a gadget or device, Laura M. and in2paints had some good thoughts yesterday about this and you should read their comments - the use should be only for a short time and only until the horse understands what you're after - it should be used as a communication and not a control device, to make a point more clear and help the horse figure out what you want. If you do this, do it with extreme care as devices and gadgets can easily cause harm to the horse and its confidence in you. Once you're done with showing the horse what you mean, the device should come off and there should be no further, or very limited, need for it. Otherwise, it's becoming a control device or a crutch, or both. Softness only comes when the horse willingly does what you ask, not when the horse has no other option but to comply. I think often people ride with gadgets or devices because they don't know how to do what they want any other way, but there are other ways, in my opinion, and I think they produce better long-term results, but sometimes those results take more time, effort and patience from us.