My hennesy web is 1". The tie-down web looked to be wider.
It looks to me like if we use the angle (theta) between the support line and the horizontal for our calculations then the formula for the static load on each line is:
0.5 * weight/sin(theta)
At least it comes out right at the extremes of 0 and 90 degrees. Hennessy states a 200 lb limit for my Hyperlite, so for a 20 degree sag (I've never measured it but it looks like 20 - 30 degrees) it comes out to 292 lb per line. Each line is secured to two strap loops, each one taking up half the load, or 146 lb.
I don't dive into my hammock, so I'll double it for dynamic load (don't be afraid to chime in if that seems bogus) so we're back to 292 times 5 per Lynn or 1460 lb. add another 500 for a fitful night of tossing and turning and that's about 2000 lb. Works for me!
Based on what Lynn said, I think his equation has a typo in it:
he had: Number of stitches = 5 * Maximum expected load * lb. strength of thread
should be: Number of stitches = 5 * Maximum expected load / lb. strength of thread.
Thanks Lynn, very useful info!