ok I see your point, I never experienced a drastic change in weight in such a short time frame,,
I made alot of bows in East Texas the humidity was high,,and it took longer to cure,,but once the bow settled in,, it stayed at that weight,, even hunting in the rain,, ok hunting I was not shooting alot of arrows( like 3d,), and that may be why I never noticed any weight change,, never had to change spine of arrow,,or anthing like that,, did notice the weight would creep up over a few weeks or months due to slow cureing time,, my main hunting bow was a sinew backed osage recurve,,it was really stable, i used it alot even in 90% humity,,,, it might be possibe that the thinner layer of sinew would be more sesative to humity,, than a thicker layer,, or might respond quicker in loosing weight,, not sure bout that one,, I started making sinew bows 20 plus years ago and have made quite a few mistakes along the way for sure,, I dont disagree with you at all ,just have had a different experience and feel you are a few layers of sinew from a Masterpiece,, but I am a little too postive sometimes,,
hope the bow works out for you however you proceed,,
