I think lighted tail caps are like crenellations and bottle openers, a result of feature creep and a needless feature. Do one thing, do it well, do nothing else, do not try to make it something that it is not. I have a knife and a bottle opener… don’t need a knife and a bottle opener on every other tool. I have an emitter on the front, and light should come out the front, not the back. If I need a way to find a light in the dark that is off, this problem has already been solved far more ideally and elegantly with glowing tape or trits. It isn’t just some flashlights, far too many things have too many lights on them, take anyone’s home, and the kitchen utilities and den cable box and modern receivers are filled with useless lights, ruining the dark of night with blue light. Car dashboards are now filled with useless lights, and they can be blinding. Technology, in a lot of ways, needs to get over how cool LEDs are, and stop sticking them on ever damn thing for no reason.
Seems that blue is the most common color for lighted tail caps, and that is even more unfortunate, as blue is brightest, resets circadian rhythms to the opposite of natural, and will cause insomnia, not kidding. If you’re going to have a light in the tail, it should be red to avoid messing with your sleep. While locking out the light, if the light will lock out (unlike my BLF Cu X5! Love the light, but with that feature the designers here jumped the shark), so locking out is a way to turn it off, but there should be some driver-based control. The way they are implemented, as far as I have seen… it is just not a mature feature, sort of an afterthought and slapped on there.