is it possible to lighten a draw weight to the point that the limbs come off? as if to loosen the screw so much that they fly off the riser?

yes, those screws will come all the way out

good thing to know before i hurt myself, haha. thanks gibblet.

If you aren't sure how far you can safely back them out, head to the pro shop.

2 1/2 - 3 full turns for most that should equal around 10 lbs . martins bows are usealy rated for 15 lbs of adjustment around 4 full turns . a scale is highly sugested / recomended

edit to say , there are no dumb questions , just dumb answers

I always recommend starting with the limbs tightened up all the way, and then back off from there.

PSE recommends I think only 2 1/2 turns out, max.
If youwant toback out more, see if you can change out the limbs for a different weight range.

Good luck.
-Bulz