Please note I'm only wearing one of those vest things to illustrate a point more easily. I wear a Charles de Blois style doublet to suspend my legs in my actual kit (as can be seen at the end), and it operates on exactly the same principle as the vest, but it would be difficult demonstrate the concept I show the audience in the CdB doublet. I explain that in the video but people keep glossing over that...
*note* this principle really is ideal for a person whose waist is in fact the narrowest part of their torso. If your waist is larger than your hips, this technique has limited use, and it will be harder to avoid transferring weight to the shoulders. The mail hose suspension idea outlined below may work regardless.
VIDEO: Suspend Your Leg Harness Comfortably
I believe the same principle can be applied to suspending maille chausses, and is still in keeping with the primary sources.
It seems to me that the most common modern solutions to this problem are a c-belt or a narrow thick leather belt. Both methods are less than optimal. Most people who have experience with a c-belt complain that it restricts movement, is uncomfortable, and in some cases prevents you from sitting down. A narrow belt will begin to cut in to the tops of your hips over time and become increasingly uncomfortable. I've also heard it suggested that a larger stiff belt like a modern weight-lifting belt could work. It will function, but I think over time it will begin to wear on the hips and dig in to the iliac crest making it uncomfortable for extended periods of time.THE KING'S MIRROR ca 1250
The rider himself should be equipped in this wise:
he should wear good soft breeches made of soft and
thoroughly blackened linen cloth, which should reach
up to the belt; outside these, good mail hose which
should come up high enough to be girded on with a
double strap;
To me this belt, that allows the mail hose to be 'girded on' suggests a solution similar to what I explain in the video. A wide strap of supple leather tightly bound above the hips and through the waist will function as a comfortable and flexible support system from which to point chausses. To achieve this the leather can neither be thick nor stiff. It functions more like a textile than a piece of cuir bouilli or a shoe sole wrapped around your waist. The key in its functionality is that it's relatively thin and easily moves with the body and by being laced tight enough, it will comfortably support all of the weight of the chausses on the hips. The width of the belt will ensure that the weight is distributed over a large enough surface area that it won't feel like it's putting all the pressure on one particular point. The relative thin nature of the belt will prevent it from having thick edges that are responsible for that digging experienced on c-belts and more traditional belts. I also believe this is in keeping with the sources.
Of course this same thing can be used with plate harness as well, and works exceedingly well for mail paunces.
**edit for clarity 7/19/15**
I've seen a lot of people trying to reproduce this idea over the past few months and I realized I didn't make clear one of the most important parts of this design. It's important to note that the shape of this belt is *NOT* just a really wide rectangle. A rectangle will slide down the body over time. It must form a kind of a cone with the top chopped off in order to function properly when worn. The top and bottom edges are curved in a gentle U shape and the top edge is shorter than the bottom. This is the key to preventing the belt from riding down or sliding over the hips once weight as pointed to it, and is what keeps it in place over long periods of time. The shape of the garment/belt will lock itself into the vertical axis and be unable to slide down because the top edge should be less than the circumference of the hips at the widest point. That combined with the friction created by the width and flexibility/stretch of the leather is what makes it work. Reinforcing the top edge prevents it from stretching and loosening on you, but the stretch in the rest of the belt is what aids it in gripping your hips and preventing slippage.
Laid out flat, this what it should look like. (Mine is configured to strap in the back, the little squares are just arming points, the important part is the overall shape):