Yup, when we rework BGA boards it's sufficient to go off the silkscreen outline of the package, if the board has one. Also the cool-down BGA effect they showed

Yup, when we rework BGA boards it's sufficient to go off the silkscreen outline of the package, if the board has one. Also the cool-down BGA effect they showed is a lead-free thing, you don't see that on leaded solder balls unless something is wrong.