Does shooting the mountains involve trekking or climbing mountains?
Yes. Typically I'm carrying 5-9 days of food plus backpacking and climbing gear. I typically don't use base camps, but rather move everyday with all of my gear, often on trail-less high traverses. Put camera gear and a tripod in there and weight becomes important.
I'd like to see more unconventional lenses developed for landscape photography with weight in mind. These full frame lenses would have top notch optical quality worthy of a D800 for instance, but would sacrifice speed for weight. Examples might include a light weight 35-70mm f4, maybe something like a 90-180mm f4 that might be a lighter and better quality lens as a 2x zoom than the 3x 70-200mm f4's are. There are lots of ideas to consider. For instance, if you're really concerned about weight while covering a broad focal length range, then leaving gaps in your focal lengths makes more sense than seamlessly joining them. Instead of 14-24, 24-70 and 70-200 zooms which leave no gaps and are somewhat redundant at their extreme ends, consider making a series like 14-24, 35-70 and 90-180. Such a series would cover very similar shooting preferences with less weight and quite possibly, better optical quality due to a 2x zoom design as opposed to 3x zooms.
Thanks for all your comments.