Yet another Thank you for the great article!
I did a few photos while mountaineering (at a quite low level - and sorry that was film era, and I didn't scan that yet) and find all said really spot-on.
Now I just hike and ski (backcountry) in the winter but find most of the article still relevant (being very seldom roped is soooo easier for the photographer...).
So I'm very curious about the Nova 170.
For the bag, it's one of the few points where personal preferences may matter (and not only photographic preferences, but also in the way you store your climbing gear).
At the time, my setup was to use a fanny pack, large enough for a small body and a 19-35, plus eventually another small tele lens.
I now use a larger Lowepro OffTrail1 (rather small by photographic standards though).
The fanny pack can be worn above the harness, and does not interfere much with it (the main attach point is above the pack, the gear carrying loops are on the side above or below the pack's belt). Of course, the volume of the bag directly before the pelvis is unpractical past a certain steepness (not that far from verticality - eg it's no problem in a AD french grade rock or mixed route, or when climbing no more than 4c french/5.5 US).
I could attach the (overly long for normal use) neck strap of the camera permanently to my main carabiner when needed.
The fanny pack is just in front of me, directly in reach. That's the main advantage, and the reason why I still use such a setup.
Another big advantage when mountaineering is that the camera is tightly secured and does not jump around when running or skiing.
As an alternative in backcountry skiing, I only use a TLZ-style pack directly passed in my rucksack belt (my offtrail does not fit because there is a pelvis harness in my ABS pack, and weight is more of a concern than when hiking). I can also add one lens pouch on the other side of the belt, making it a bit more practical photgraphically speaking.