My apologies for not first putting the previous post on a 3# boot/crampon combo into context. The study cited below is worth a look if you find this subject interesting. The first quote is from this web page:
I have only looked at the boot weight info on that web page because it is old info I wanted to share and have not read the rest of the page so as always "buyer beware".
"Keep in mind that for every 1 lb of footwear, it's like carrying an extra 6.4 lb of weight on your back." [Authors: S. J. Legg a; A. Mahanty - This study was conducted in part fulfilment of an MSc in Human and Applied Physiology, London University 1982. Published in: Ergonomics, Volume 29, Issue 3 March 1986 , pages 433 - 438]
'Ergonomics' is a widely distributed journal, owned by 616 libraries in US and CAN, according to the WorldCAT. Many research universities have it available. 'Ergonomics' is published by the Ergonomics Research Society. They do government funded, peer reviewed, research worldwide, on fatigue, industrial and medical ergonomics, flight simulators, body armor, etc.
"Shoe Weight, runners 28oz, boots 70oz (my Trango extremes are just over 32oz per boot or 64oz)
Equiv. work for this Weight on you back, runners=11.2 lbs, boots=28 lbs"
I found from guiding that most folks are hard pressed to carry 25% of their body weight day in and day out. That means a 200# man gets 50 lbs in their pack. A 120 # woman 30 lbs in hers. Plus what ever they are wearing. If you want to stay healthy get under that number. Try doing hard technical climbing and it is even less. 20% for a "big" load or 40# for a 200lb man.
Sure you can carry more but you'll pay for it one way or the other.
A typical dbl boot and technical crampon in my size will be around 12 lbs on your feet per pair or 76 lbs on your back. Now you can see why I want to cut my boot weight to 6lb for the pair or what adds up to 38 lbs.
But as John implied in the previous post's comments if the crampon and boot combo you chose doesn't make your climbing easier you should look for a better combo and stop worrying about the weight.
As much as I like them I no longer climb in Dartwins because I found them too unstable on easy terrain. The weight drop of the "sport" style crampon is not worth the extra effort required for me to use them no matter how light they are.
So I work at getting my boot/crampon combo as light as possible. But I also work at getting all my gear as light as possible. I will not sacrifice weight for performance. Durability? Sure, depending on the economics involved sort out. 5 extra .oz on your feet is worth a full 2 lbs on your back. Think about what 2 lbs is worth in your pack?
I could loose extra body weight by the pound and worry less about the weight of my gear. But there are climbers out there who have no extra body weigh to loose. Those are the climbers who can best take advantage of lwt gear.
Or as a couple of my buddies like tell me when I start fixating on gear weights, "Just train harder and it won't matter." But in reality everything matters.
Same reason we train, watch our diet and buy the best gear possible. It is all in the details and it all matters.
Robson Southface approach update.
6 hours ago