Um...
I did, in fact, answer my own question.
About a month before I went back to Portugal, I decided to trade in just about all other cameras I own, as I was going to finally commit to the Leica (in Portugal, pronounced "Leeka")
So I got a Noctilux, a 135 Elmarit, and a Contax IIIa Colordial (and working meter) which takes the CV 21mm and who's shutter is rather better than the Kievs...
Anyway.
It's a "Yes," by the way. The Noc is heavy, but completely usable as a normal lens. It does have its idiosyncrasies, but it's not nearly as hard to focus right as many have claimed. I have lots of practice on cameras without the sharp-edge spot of the Leica, and found the Noctilux just as easy to focus as any other. No blown shots for focus, exposure, or any other reason- a record for me.
It's a nice lens. I am used to carrying around a Mamiya Universal and though the Noctilux won't ever replace that wonderful f/2.8 100mm, it certainly falls in line next to the other lenses I have for my MP.
Bring along an 8x ND filter, a 60-62 step up ring, and slow film. Wide open in the daylight is fun!
I've found that I do spend lots of time in restaurants and other dim places, so it's a perfect all-arounder for me.
The attached picture is Tri-X shot at 1250, with a Wide Open Noc for exposure, in a sushi bar near the Ponte Salazar (apenas bricando!). A touch grainy, but not objectionably so. Not my best work, but the first out of the soup.