This is a request to re-open the issue #0018338 (http://feedback.arma3.com/view.php?id=18337). It was auto-closed for being over a month old.
The issue in that report is still ongoing. Lightpoints will not stay affixed to their assigned locations on moving vehicles, causing them to jitter all over the place. I would request that the devs provide some way to attach lightpoints in the same way that the vehicle headlights are attached, since they work without an issue (so it's obviously possible).
Simply...
_light = "#lightpoint" createVehicleLocal visiblePosition _vehicle;
_light attachTo [_vehicle,[0,0,1]];
and then set a reasonably large flare size so you can actually see the physical lightpoint and then drive at >100km/h and watch it become elastic.
In addition to light points created with createVehicle, i am experiencing this with a pistol-slot weapon using class Flashlight{} when benched on a flying heli (single player) so this is more than just an attachTo issue.
light point (including visible 'bulb' (scale[]) stutter upto 2m behind its expected point, if facing forward, will cause unit with flashlight & parts of helicopter to be rear-illuminated.