Interesting thread. I am not going to take the high ground as my relatively new horse now works better in a caveson. Previous horse would run through the bridle but the flash was not done up tightly. He could open his mouth a bit and that seemed to work. I like the crank as I like the padding but like a previous OP, it is not done up tightly.
I prefer a horse with a nice soft mouth, never, ever have put a gadget on a horse.
I did use a running martingale after one observer said I was brave to ride her without one, and I'm not brave lol.
There was one racehorse ridden in a net, and on its own, but it was a bit of a loony and I did not ride it.
I once "broke" 50 Shelties with neither saddle nor bridle, so after that I reckoned that bits were just a luxury!
In my younger days I thought nothing of riding with no saddle or bridle, there was no H&S, and we were too lazy to walk them.