I think that is a glitch as well,
On some other golf apps . There are sometimes many others playing the hole/course at the same time . Other golf arcs are visible frequently . Maybe that is the case here ?
I agree that these are "glitches" (using this term to describe some time of "hiccup" in the programming code). It is interesting that it does not happen to everyone nor on any consistent basis. Curiously, I am noticing it is occurring much more frequently. I wonder if it is more frequent during peak times of heavy use and that could be the cause. I dare say it may be time to for WGT to upgrade its hardware to accommodate the expansion as this may result in an increase in cost of balls and equipment.
I do not believe the lines are "ghost" arcs from other golfer's struck balls. The lines are the ball path directional lines pre-programmed by WGT for that specific ball location, distance and pre-selected club.
It appears to me that the lines depict two different events.
In the example posted above, the solid color line, I suggest, is WGT's programmed flight path of the ball given the club WGT initially selects for you. Ordinarily, this line would not be displayed until you hit the left mouse, or equivalent, key when aiming a shot with the cursor. It appears in some instances; the line is visible to other players. In the above example, the player has selected a different club. The multi- colored line is the (effect" trail" coming from the struck ball and reflects the balls actual flight path. If the player was not using a ball with the trail, the solid line would still appear while the ball took a different path. (I do have a picture which reflects this, where you see the ball on a different trajectory of the line but have not posted it).
The below pic is the same player, same ball position as the above pic, but the player has not yet changed club selection. First, the line should not be viewable by other players. Next, it should appear while aiming and not just be there. As can be seen from the above pic (in my previous post), once the ball is struck, this line remains visible.
The second "event" where I have seen "ghost" lines is on the putting green. The opponent's "aiming" line appears and remains when it is my turn to putt.
Recently, when a friend and my balls were both on the green, on opposite sides of the pin, he putted first, and the line of his putt was shown both during his and my putt.
Below, the above aiming line remains in view when I am putting -
The line is definitely the "aiming" line or "WGT pre-set path" and not the actual path of the ball. As can be seen in the above pictures, the red line is straight to the hole. Yet, as seen in the second picture, which shows my opponents ball, he missed the putt.