I think you never actually grasped what we've been saying about lobbing. The points of my and Thearos's posts on lobbing have been to show you that "a shot that is purposely underpowered to achieve a higher arc" is not a lob. Again, a lob is a throw that accounts for bullet drop. Not a short range throw pointing high so it will drop more, and not a short range throw that is softly tossed. A lob is a shot that has been thrown at the most effective speed that the slinger can produce and is allowed to drop, instead of the slinger pushing themself past that to make the throw faster and flatter when slinging at longer distances.
Now, throwing with everything you've got is not efficient and is not a good idea. If you do that, dial it back slightly and your accuracy will improve because your technique will improve. This may be the source of confusion.
Rat Man wrote on Nov 26
th, 2013 at 8:24pm:
... also most of us have found that shooting with full power does cost some accuracy. The general consensus seems to be that approximately 75% or so of one's full power will give the best accuracy with a negligible loss of power.
Letting a stone fly long enough and slow down enough to start dropping will not have a noticeable effect on the terminal ballistics as long as it doesn't skip off the target at a shallow angle. This is because momentum is what determines terminal ballistics. If KE did, then slowing down over a long distance or being slow enough to noticeably drop WOULD be a bad thing. It just isn't in real life. Just to reiterate what I've said about KE vs Momentum, as well.
Point blank -by definition- is the distance at which a shot will not miss because of wind, drop, etc, after it has left the weapon. They only way you can miss the target with a sling at point blank range is with a botched throw. Equivalent to a mechanical failure in other weapons. At point blank range neither a lobber nor a flat-liner (better than whanging, Dan?) will notice drop. It is past this that the difference becomes noticeable. So, point blank can be 20 meters.
What I'm getting out of this is that you and Dan both lob at medium-long distance and you haven't noticed yet that your accuracy has plateaued at short distances. If you aren't actually lobbing all along.