Thanks, all, for having a look and for your kind words.
Peter - The B&W conversion is fairly straightforward, but it really pushes LR to the limit and can, as Chuck pointed out, look a bit contrived. In LR, I convert to B&W and typically apply a slight warm/brown tone using a Split Toning of Highlight Hue 0, Sat 0; Balance of -50; Shadow Hue of 48, Sat 12. I will often check the "Auto" version, just to get a sense of what the LR algorithms "think" - often they are quite good. From there, I'll either go back to 0s or adjust the Exposure to levels which bring out detail, but also knowing what's coming next...
With B&Ws only, I often work backwards to the recommended "top down" method of adjustments. You have to remember, what I'm working towards is re-creating the "vision" or "visualization" of the scene I saw when I made the photo. While I am much more of a literal photographer than an imaginative one (I try to be true to the structure of the scene), I am also trying to convey more than just the scene – the light and the feeling that goes with it being there at that time.
So, for B&Ws, I apply a Clarity adjustment of between 50 and 100, then I bring the Blacks up so there is just some clipping, then adjust the Shadows upwards to bring out detail as needed. I'll often give a similar treatment to the Highlights by raising the Whites as high as possible with perhaps just a small amount of clipping (if there were true whites in the scene), then adjust the Highlights downwards, typically to maximize the tonal separation in them. I then walk away from it and revisit the photo a few days later. Sometimes I'll make a print (using Moab Entrada Rag Natural, which needs a bit more contrast to sing) to check tones. Prints are my ultimate goal here. I've attached a Develop module Basic panel for "The Trail" (the original, not the one here).
Chuck - You're right, I did push the two B&Ws a bit far. As I said above, prints on Moab Entrada Rag Natural are my ultimate goal, so a boost in Contrast is needed. Both were high contrast situations with a real "edge" to them. My goal was to maintain that edginess. I also wanted to ensure the rock was more than just "there"; I wanted it to "speak", so I needed it to look more alive than dead. Bumping Clarity has a way of doing just that. I've gone back and tried the same shots with reduced Contrast, Shadows, Blacks and Clarity and while they look more realistic, to me the rock is not alive enough, it's too muddy (see attached). Perhaps there's a balance there I'm missing.
David - ƒ11 is the sweet spot with this lens (in fact, all of the Nikkors I own) and I try to make best use of it. Typically, however, I like to get in close and am pushing DoF to the limit so use ƒ16. To me, there are times when the gain in DoF outweighs the loss of overall acuity, especially when much of that loss (or all, perhaps) can be gained back in sharpening.