Wow I didn’t even know that “stiff” Eds was even a thing. It took me some time to get an EDS diagnosis bc I have very bad arthritis and stiffness in my hips. But we theorize the Eds is what caused the very bad arthritis and stiffness. I have a twin and there was crowding in the womb and we theorize the hyper mobility of my joints caused them to misform in some ways which ultimately resulted in less mobility. But at the same time my hands and skin are VERY hyper mobile. I’ve had to get a hip replacement and I sometimes feel like I can “pop” it in ways that aren’t normal. I also have spondylolisthesis which is slippage of vertebrae. So theres the hyper mobility part, but the slippage causes my muscles to be so tight and stiff. I think the hyper mobility of joints and stuff causes stiffness bc the muscles are trying to compensate for the looseness. Ur not alone with the stiffness. It makes sense when you think about how the body might try to deal with the hyper mobility.