The gravity on your planet is slightly lower than on mine.Somehow, I doubt technique is going to make much difference when walking 30-50 yards uphill with double X7-100s. 70lbs is 70lbs, technique isn't going to change it, and that doesn't take manifolds, plate, lead, or other gear into consideration.
My double Faber LP 95s weigh 81.5 lbs empty and my double X7-100s weigh 73.1 lbs empty. When you add 200 cu ft of gas, the weights climb to 94 lbs and 86.6 lbs respectively. When you add a back plate/harness, wing, regs, reels, can light you will be getting close to 130 pounds.
My advice is NEVER weigh your doubles.
But technique really does make a difference, as you start learning ways to avoid lifting them and to minimize the effort when you have to. And it is good to know that teen age children make great tank sherpas! (I need to get me another one since the first one got too big and moved out.)
Even if you have to carry them yourself, you have to consider that some women divers do it all the time. The love of my life dives with double 95's and she has carried them in and out on some fairly rough trails to some of the less well developed basins, so it's pretty hard for me as a full grown man to complain about mine.