Around here the lighting above tables is different in different places. So the reflections on the balls, shadows, etc. will be different depending on which table you are playing on.
So for this reason, I never thought any aiming system based on lighting would be good for all situations. Might work good at one place, but not the same somewhere else.
As to the different lighting, some lights are higher, some lower. Some light up the center of the table, others light up the entire table (i.e. There may be 10 fluorescent lights above one table and the light fixture is almost the same size as the table). Then the "TV" tables which have many many "TV studio" bright lights shining on the table from all directions.