Turns out I was right. It does look good in monochrome.
click to enlarge, or see it on Flickr
Shutter Speed: 6 seconds
Focal Length: 36 mm
The Lightroom tools for monochrome are extremely intuitive, even when working in RAW. In fact, had I not known, I wouldn't have been able to tell that I was working in RAW. When I was happy with my result, I exported to JPEG. Just for comparison purposes, I did my best work on the JPEG with Photoshop to see if I liked that result any better. It wasn't even close. RAW is champion when it comes to monochrome. I couldn't get close to the amount of contrast I wanted without severe posterization.
My last step was just to experiment with a vignette in Photoshop until I liked it. There are a few things I feel I could have done better, and a couple of things I thought I wouldn't like, but turned out really good. The pawn isn't in sharpest focus. It's pretty close, but I should have been paying more attention when I set the shot up. The aperture could have been stopped down just a little more, to achieve the really distinctive hierarchy of levels of focus I was going for. And I didn't think the unfinished tops of the pieces would look good, but I think they add some character to the shot.
I may try a redux of this shot sometime with a more carefully set-up environment, etc. But now I know: for monochrome photos, don't bother with anything but RAW anymore.