Originally Posted by Adam
Top of the trajectory is the top of the trajectory. Perception doesn't enter the equation, only physics.
You can choose to align your sighting system with this point or with another point. If you choose a point lower than apogee, the sighted rig will be "zeroed" at two ranges.
When set to touch the trajectory at a single point, a higher sight line relative to the bore will touch the trajectory curve further away than a lower one.
... is what you meant.
When the scope line is significantly higher that the barrel it starts to look down the trajectory thus placing the "top" of the trajectory further away.
But of course you knew that.