Those are called Brannock devices. (my head is full of useless information!)
My first hammock was a smallish 4.5x9 parachute hammock. That darn thing is STILL the most comfortable hammock I have (out of 5!) I can hang it ANYWHERE, ANY WAY and it's comfortable! So, I think you're on to something there. I don't know if it's the proportion of length to width, or the proportion of length to the height of the user or what, but I agree with your findings, Catavarie. Thanks for the write-up!