I have been using the visual suggestion of the zippered built-in bug netting to suggest the sag.
I inverted or removed the spreader rods, got out a tape-measure, and found that in following that visual guideline, I have been hanging much tighter than the 5/6 = 83% of hammock length solution than I thought, around 100 ridge-line inch length for a 108" hammock once I measured it ( = 93%. ). That was the tightness that had the bug netting just loose and the hammock "looking best".
Has anyone else explored greater sag than what is implied by the bug-netting length, even though that leaves fabric and netting above the gunwale somewhat loose?
I'm suggesting that Clark hammocks with beds identical to those using spreader rods are possibly being set by users with more sag and greater / different comfort, because the netting on those without rods is held up and gently taut by the bungees.