I think you have to make a distinction between shadows and blacks. Shadows are dark but there should be detail. Black may have zero detail, even if not clipped. For me the key is adjusting exposure and opening the shadow. The black slider is used only to establish a base black necessary for good "scale".
When I’m editing in Lightroom, pretty much the first thing I do is try to gauge the exposure, first by looking at the image itself, but also by looking at the histogram. I can see if the histogram is bunched to the right, maybe even not touching the left wall of the box (and if I’ve ETTR then it should be bunched to the right), I’ll most likely pull the exposure slider to the left, watching to see the histogram “center” more or less. I don’t think you can get real scientific with this since it is an art form, but I like to approach it with some science in mind, but the real proof of the pudding is in the image. If it looks too dark or light it probably is regardless what the histogram "says."
I am still waving my white cane as I navigate the mysteries of Lightroom, but I am perceiving there is a difference between the shadow slider and the black slider. It’s a subtle difference. My workflow has evolved to the point that I adjust shadows and highlights before I do blacks and whites. I am not at all averse to throwing the shadow slider all the way up (right) to open them, and sometimes the highlight slider all the way down (left). That compresses the contrast range and I can see it in the histogram, which broadens and maybe flattens out, but also I can really see it in the image as the shadows open with detail, plus more detail in the highlights. The overall exposure may need a slight adjustment at this point. This is not a go-to either; you have to gauge it based on what it should look like.
For me, the black and white sliders are used almost always last. I turn on the clipping indicators, hit the ALT or OPTION key, and slide the white slider to the right until I see the barest hint of red (highlight) clipping, then back it off until it disappears. The black slider goes left until I see the barest hint of blue (clipping), but sometimes I will leave a little of it as a true, true black puts a kindofa “base” on the picture. I have felt that adjusting the blacks and whites until they are alllllllmost clipped has very little affect on the look of the highlights and shadows, but I don’t know precisely why since they are all global adjustments.
So my thinking is, it’s not a matter of better, but different. I like my shadows open with good detail but I also want a solid black somewhere. Ditto with the highlights, good detail but with an almost clipped white somewhere. This is basically a bastard zone system.
As far as noise is concerned, I don’t think it makes a difference. Noise is mostly a function of ISO: the higher (“faster”) the ISO the more noise it tends to generate, exactly like film. If you’re forced to use a high ISO it will increase noise, degrade sharpness, may even have an affect on colors, but it’s all tradeoffs. If you’re working in reasonable light it’s easy enough to damp without doing too much damage to sharpness. The main thing I grasp about ETTR is that by giving more exposure to the shadows you gain detail and reduce noise at any ISO. You are, as we used to do in B&W wet days, “exposing for the shadow and developing for the highlight.”
Almost forgot: https://improvephotography.com/46492/sh ... fferently/