I've tried a similar approach with my brother's godfather's old 2 quart canteen and a canvas satchel. Maybe I had too much weight, but it quickly became uncomfortable for my shoulders and I developed some severe tender spots and redness on both shoulders. I suppose if the satchel straps were padded (they were wide enough), it may not have been so bad, but then lugging two full quarts of water on the other shoulder isn't the best thing either, especially when its strap is maybe half an inch wide.
I don't use this method anymore, and I don't often carry that satchel. I prefer the humble day pack - the weight is distributed evenly on my shoulders, and the straps are wide and padded thick. Plus, mine has a sternum strap and a padded waist strap for heavy loads or long treks. I'll take that comfort over "sucking it up" and ending up with sore muscles. I think our forefathers who used the canteen-haversack system, especially in the military during the Seven Years War, Revolution, War of 1812, Civil War, right up until WW I, had to "suck it up" and put up with the discomfort, else there was no way to carry their loads (except by horse when moving camps). This, combined with other miseries, would have made them tough people, though doubtless some became suffering wretches.
Through my own experimentation with "traditional"/historic kit, I have come to the conclusion that it is certainly not for me...I will take modern ingenuity any day. I think Humakt put is best:
And to add, the previous generations didn't have the wonderful materials that we do today, and they had to make do with what the limited materials that were available. Now this doesn't at all mean that historic kit doesn't have a place today. It does - with historic reenactors, and I have great respect for them. I just cannot see the reason why Bushcraft has to be clouded with the bygone days of early colonial America, neglecting how far we've come and how much our knowledge and materials have evolved. But that's just me, I don't see anything wrong per-se with folks trying out historic kit, but it does bother me that there still remains an argument that "the old ways were better", and those promoting this defunct ideology discourage modern developments, convincing a majority of newcomers to the outdoors that they need that boy's axe in their kit, a queen sized wool blanket, and so forth. And before you know it, they've invested hundreds if not thousands of dollars in something because they are told it looks cool, and that "proper woodsmen" need to be equipped only with "proper" kit.
All that aside, I really like quality leatherwork...your efforts look outstanding
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