Something to ponder... Rule 17-4 Ball Resting Against Flagstick. Most of us would have had this happen or seen it and know if the Ball falls into the hole when Flagstick removed the Ball is holed. Sounds fair. Similar to situation discussed in this thread, the Ball is touching the green obviously prevented from falling into the hole by The Flagstick. The Flagstick is a “movable straight indicator” rather like a movable obstruction but with special status.
Why should it be so special that a stick or a movable obstruction clearly preventing a ball falling in the hole be treated differently.?
The answer seems to be “it just is, don’t bug me” . A Rules expert might give a well thought through reason for the specialness but it wouldn’t pass “The Pub Test”.
This sort of problem which seems quite unfair to players is a reason The Rules and the people making them seem out of date and inflexible.
We don't yet know what the R&A's ruling is but I am awaiting it
But I must say this is a good analogy.
For a ball to fall in if an object is preventing it, the centre of gravity must be beyond the edge of the hole. The object must be nearer than the diameter of the ball.
Like a leaning flagstick. Or, as in the original posting of this picture, the twig. I have checked and the poster said it would fall in if the twig was removed. That means the bottom of the ball was over the hole.
So the ruling for this twig should be the same as the leaning flagstick 17-4 if the object is a MO. In equity of it is a LI.